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B56133B56133 ResearchResearch doesn’t doesn’t have have toto be be heavy heavy.. TheThe Science Science Magazine Magazine of of the the Max Max Planck Planck Society Society2.20192.2019

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Lab beneath white sails

The Eugen Seibold is anything but a normal yacht. With its clear, elegant design it may resemble a luxury yacht at first glance, but anyone taking a closer look will soon notice a number of striking differences. The short cockpit, large deckhouse, high rail, and in particular the large open area in the aft part of the ship featuring a very prominent A-frame for handling large and heavy measuring instruments, all point to the fact that the Eugen Seibold is a working vessel. With its length of 22 meters, a weight of 44 tonnes including all fittings and equipment, and a relatively small sail surface of just under 300 square meters, this yacht is certainly no “high-performance boat” in a sporting sense, but all the more from a scientific point of view. Everything on board is geared towards efficiency and flexibility, and laboratories take up more than half of the indoor area. The vessel can be sailed reliably by a small crew of just two or three people, even on the high seas. Scientific work on deck is facilitated by lightweight measuring equipment and the hydraulically pivotable A-frame. Comprehensive sets of research data can therefore be collected at comparably low cost, both for long-term observations and on shorter excursions. The idea of Gerald Haug from the Max Planck Institute for Chemistry to create a research sailboat could be put into practice thanks to the Werner Siemens foundation that funded the construction of the yacht. Haug’s research target is to achieve a better understanding of the biogeochemical cycle of the oceans. In other words, the synergies between the sea’s physics, chemistry, and biology and the marine atmosphere. Haug and his team want to use the sailing yacht to take contamination-free air and water samples. While continuous contamination of the local environment from diesel-powered vessels with metal hulls is unavoidable, research operations on the Eugen Seibold can be conducted without using the diesel engine for up to ten hours. This is possible despite the considerable energy consumption of the extensive high-tech equipment on board, thanks to a hybrid engine and a powerful high-voltage battery. Photo: Michael Amme

2 | 19 MaxPlanckResearch 3

Contents

Designs: When the boundaries between human and machine become 18 ENERGY 10 blurred, new ethics are required.

18 The beginnings of the biobattery PERSPECTIVES The energy supply of the future has a storage problem. In order to store 70 years of academic freedom excess power from wind turbines and solar power systems for times 06 when there is not enough electricity availably, high-power batteries and 06 Full steam ahead! capacitors are required that should be made from the least toxic, most 07 “V iruses can quickly alter an sustainable materials possible. Scientists at the Max Planck Institute entire population” of Colloids and Interfaces are working to find a solution. 08 New York, Bristol, Tokyo 26 Solar fire in the stellarator 08 Exemplary further development 09 A river under human influence Harnessing solar fire on Earth is something that humans have dreamed of for many years. In fact, nuclear fusion in a reactor on Earth would 09 On the net provide an entirely new source of energy. At the Wendelstein 7-X facility, researchers at the Max Planck Institute for Plasma Physics are exploring one approach to this form of energy generation. VIEWPOINT 34 A greenhouse gas to fuel the chemical industry 10 Digital humanism Di gitization is literally drawing Carbon dioxide, of all substances, could help the chemical industry closer to our everyday lives. For a reduce its climate footprint. Using energy from renewable sources, long time, the issue of ethics has it could be incorporated into the building blocks of plastics and other been on the table that keeps the products – if suitable catalysts and production processes can be found. use of artificial intelligence within This is what a team from the Max Planck Institute for Chemical reasonable limits. Our author Energy Conversion is hoping to achieve. advocates reviving humanistic ideals for the digital world. ON THE COVER Rays of light for the energy transition: in future, regenerative energy sources are planned as a replacement for coal, gas and mineral oil. Here, nuclear fusion could offer an alternative to power from wind turbines and solar power systems. FOCUS The tracer of an electron beam in a plasma shows that a magnetic field confines its charged particles as needed, which melt in a fusion power plant and would release 18 The beginnings of the biobattery large quantities of energy. While fundamental physical and technical questions remain unanswered when it comes to nuclear fusion, to date there are no suitable 26 Solar fire in the stellarator energy storage facilities for expanding wind and solar power. Batteries from renew- 34 A greenhouse gas to fuel the able materials or chemical products produced from carbon dioxide could help here. chemical industry Cover: Matthis Otte/IPP; photos on this page: C. Dietl (large image), Alamy

4 MaxPlanckResearch 2 | 19 Success: The Event Horizon Imprisoned: Pitcher plants from Measured: Tanja Michalsky is in- telescope has delivered the first Southeast Asia entrap flies vestigating the stories that historic 50image of a black hole. 60and enjoy a hearty meal. 74 geographic and city maps have to tell.

SPECTRUM BIOLOGY & MEDICINE REGULAR FEATURES

42 3D movies from cell membrane 60 Fill up the bowl! 03 On location 42 Mo lecule from the early universe Le ghold traps, limed rods, pit traps - 16 Post from the Antarctic insectivorous plants have come up 43 Di et influenced the development A paradise in white and blue with unusual strategies to obtain of languages 80 Flashback additional nutrients. At the Max Lower pension, shorter life A method that lends wings 43 Planck Institute for Chemical Ecolo- 43 On the trail of the Denisovans gy, researchers are investigating 82 Max Planck Community 82 Joining the Square Kilometre Array 44 Genetic defects without how pitcher plants from Southeast 83 Remembering Suzanne Eaton consequences Asia entrap and digest their victims. 84 Ma x Planck Survey on work culture Are fish aware of themselves? 44 and atmosphere 45 Lif e-saving turnaround MATERIALS & TECHNOLOGY 85 Wol fgang Baumeister wins in energy policy Stifterverbandspreis 2019 45 18 Earth-sized exoplanets 68 Programming fairness 86 United with one voice discovered In the future, it will be more and more 87 Research Establishments 46 Monkey hunting ensured survival common for computers to make deci- 87 Publisher's Information in the rainforest sions about human beings – whether 46 In sulin protects against they are granting loans or assessing colorectal cancer applicants. However, automated 47 Chimneys in the Milky Way systems occasionally discriminate Black holes against individual groups of people. 47 So cial uncertainty also puts Scientists at the Max Planck Institute 50 Overview chimpanzees under stress for Intelligent Systems hope to A portrait of a black hole 48 Fr uit bats are reforesting change this situation. 55 Interview African woodlands “An astounding coincidence 48 The roots of apple trees with theory” 48 A leap towards superconductivity CULTURE & SOCIETY 57 History at room temperature The mystery of the 74 The art of orientation dark bodies Personal portrait: Tanja Michalsky SPECIAL Cover: Matthis Otte/IPP; photos on this page: C. Dietl (large image), Alamy Photos: EHT collaboration; Anna Schroll; Bernd Wannenmacher

2 | 19 MaxPlanckResearch 5 PERSPECTIVES

70 years of academic freedom

German research institutions launch a campaign to mark the anniversary of the Basic Law

Open to discussion: at the Zeit Forum in March, Max Planck President Martin Stratmann (middle) joined Zeit editor Andreas Sentker, Nadia Al-Bagdadi from the Central European University, Anuscheh Farahat from the Friedrich-Alexander-University (FAU) Erlangen- Nuremberg, and Ulrich Blumenthal from Deutschlandfunk to debate the question: academic freedom – a success story?

pieces will highlight the importance of independence in research and teaching – especially for basic research. At the same time, however, the scientists will take a critical look at their own developments and draw attention to potential risks to academic freedom. In May 2019, Germany celebrated the responsibilities it imposes. Originally Among other topics, there will be discus- 70th anniversary of the Basic Law, prompted by the Max Planck Society, sions on the permissible scope of human which states in Article 5 that “sciences, the campaign “Freedom is Our System. genome research in the age of CRISPR/ research and teaching shall be free.” Together for Science” is an initiative of Cas9 and the need for regulatory mea- German’s scientific community is using the Alliance of Science Organizations sures in relation to autonomous, self- the anniversary as an opportunity to in Germany, which brings together ten learning machine systems. The launch discuss the resulting success stories and important German research institu- event in March was devoted to examin- the opportunities and risks that this tions. Over the course of 2019, a series ing the responsibilities associated with freedom presents, as well as asking what of events, talks, debates, and opinion new medical treatment methods.

Full steam ahead! The MS Wissenschaft will dock in 27 cities across Germany and Austria

Since mid-May, the MS Wissenschaft – a cargo ship with an on-board science center – has been undertaking another grand voyage. After an inauguration in Berlin, it is sailing to 27 cities via navigable rivers and canals. Covering almost 600 square meters, this year’s exhibition is all about artificial intelligence and examines the opportunities of machine learning, the intelligent analysis of large volumes of data, and the interaction between humans and machines, to name just a few aspects of this multifaceted subject area. Over 30 interactive exhibits invite visitors to embark on a journey of discovery, with opportunities for active participation and also for reflection. This year, three Max Planck Institutes are taking part with a broad range of research topics. For example, the exhibit Der Körper denkt mit (“The body thinks too”) from the Max Planck Institute for Mathematics in the Sciences illustrates that even artificial intelligence isn’t independent of the body or its surroundings. The HyperDiver diving robot from the Max Planck Institute for Marine Microbio logy uses machine learning to determine the biodiversity and state of health of coral reefs. Lastly, the exhibit from the Kunsthistorisches Institut in Exhibition on board: with a focus on the subject of artificial Florenz explores the idea that the concept of a non-human form of intelli- intelligence, the MS Wissenschaft will be on a tour around gence is a long-standing source of inspiration for human creativity. Germany until early October – and exhibits from three Max Planck Institutes are going along for the ride. https://ms-wissenschaft.de (in German) Photos: Phil Dera (top); Ilja Hendel/WiD (bottom)

6 MaxPlanckResearch 2 | 19 PERSPECTIVES

“Viruses can quickly alter an entire population”

Guy Reeves on the release of genetically modified organisms into nature

Thanks to new techniques such as the is the subject of much discussion nowa- CRISPR/Cas9 gene-editing scissors and days – operates at a snail’s pace. What’s the so-called gene drive, researchers can more, the host range of a virus can be very edit the genotype much faster than before broad, so it’s sometimes difficult to pre- and propagate these changes in a short dict which species a virus is able to infect. time, even in large populations. In the laboratory, genetically modified organisms Are you against the release of genetically have been used successfully for some time modified organisms under all circumstances now – for example, in basic research and unless they are agricultural crops? drug production. Now, there are also plans No, not at all. It’s not about standing in the to release them into nature. Guy Reeves way of new technologies. But we have to from the Max Planck Institute for Evolu- be careful and weigh up the potential risks Guy Reeves tionary Biology in Ploen views the release and benefits. Accordingly, infectious ge- of genetically modified viruses with par- netically modified organisms in particular ticular concern. should only be released following careful an animal with generations as short as testing. In general, I also don’t think it’s those of the mosquito, it could take the There are various projects in which scientists or sensible to use viruses whose risks are gene drive eight years or more, under companies want to release genetically modified hard to control if there are alternative ideal conditions, to make a population organisms. What you think about that? techniques that can achieve the same incapable of reproduction. Moreover, Guy Reeves: What particularly worries me objectives. For example, the number of from our experiences with insecticides, is the release of infectious viruses that malaria infections can also be reduced by we’ve learned how quickly insects can have been genetically modified to bring using mosquito nets and by improving adapt if the selective pressure is strong about changes in mammals’ immune sys- people’s living conditions. enough – and if they developed resis- tems. Many such viruses have already been tance to a sterility gene, it would be like developed in order to make mammals im- There’s a sterility gene that’s intended to wipe having six winning numbers in the lot- mune to diseases or even to sterilize them. out mosquitoes and therefore to prevent the tery. I’m certain that large insect popula- A genetically modified virus that spreads spread of malaria. How does that work? tions will adapt to a gene drive of this throughout wild rabbit populations in or- A gene of this kind causes female mosqui- kind and deactivate it. Mosquito are very der to provide them with immunity to two toes to produce sterile daughters. Their unlikely to be exterminated in this way. diseases was tested on the Balearic Islands sons, on the other hand, are capable of in Spain in the year 2000. In Australia, an- procreation and continue to spread the Are the current laws governing these kinds of other virus has been produced that can gene throughout the population. How experiments adequate? sterilize mice – but it is yet to be released. ever, this only works if the mother has The regulatory authorities face an enor- Another example is a research project two mutated copies of the sterility gene. mous challenge. They have to consider ex- by the DARPA research agency of the U.S. In that case, she will actually only have tremely complex mathematical models – Department of Defense. This uses insects half as many offspring, and the mosquito a difficult task even for well-equipped to transmit genetically modified viruses population will shrink – although mosqui- authorities in industrial nations. But to corn and tomato plants. At present, the to populations are often huge, and it many of the prospective projects will experiments are still being conducted in would take a long time for them to die out affect emerging economies that are not secure greenhouses. However, if viruses in this way. After all, two copies of the equipped for this sort of thing at all – and, of this kind are to be intentionally re- sterility gene have to meet in a mosquito of course, viruses and insects don’t obey leased into the environment, then the for the insect to actually become sterile. national borders. procedure will have to be tested very carefully indeed. Although these technologies A phenomenon known as the gene drive could Interview: Harald Rösch have already reached an advanced stage, accelerate this process. the process of testing them is only just Exactly. The gene drive mechanism en- getting started. sures that all offspring of a female mosquito receive two mutated versions of Why are viruses so problematic? the sterility gene, even if she only con- Almost no other biological system can tains one copy. The population would affect an entire population with such therefore shrink much faster than nor- speed – that is, within a single generation. mal. However, the gene drive is nowhere

Photo: private In comparison, the gene drive – which near as fast as many people think. Even in

2 | 19 MaxPlanckResearch 7 PERSPECTIVES

Max Planck Center Partner Institute

Getting started: the Co-Directors of the Max Planck Center in New York, Melanie Wald-Fuhrmann and Catherine Hartley, Hugh Brady, President of the University of Bristol, Max Planck President Martin Stratmann, and Klaus Blaum, Co-Director of the new Center in Tokyo (from left).

for life. The dimensions in question are New York, Bristol, Tokyo even smaller at the Max Planck-RIKEN- PTB Center for Time, Constants and Three new Max Planck Centers founded on three different continents Fundamental Symmetries, which is a collaboration by a total of four partners: The Max Planck Society has further ex- memory, and decision-making on the the Max Planck Institutes for Nuclear panded its collaboration with top inter- other – and researchers plan to study Physics and Quantum Optics, the Japa- national partners, opening three new interfaces between these areas through nese research institute RIKEN, and the Max Planck Centers in spring 2019. experimental work. At the Max Planck Physikalisch-Technische Bundesanstalt The first of them is the Max Planck Bristol Center for Minimal Biology, re- (PTB). One of their objectives is to devel- NYU Center for Language, Music and searchers want to construct artificial op clocks that are even more accurate Emotion in New York. This Center cellular skeletons and develop na- than today’s atomic clocks, with a view combines the traditionally indepen- noscale molecular machines. By doing to determining natural constants more dent research areas of language and so, they hope to gain more accurate in- accurately and investigating the symme- music on the one hand with emotion, sights into the building blocks needed try between matter and antimatter.

Exemplary further development Federal prize for a highly parallel drug analysis method developed in Goettingen

The development of new drugs is a very laborious and expen- Successful technology transfer: sive process. When a new substance is discovered, research- Moritz Rossner from the Max Planck ers must determine how a large number of molecules – Institute for Experimental Medicine. so-called targets – react to it within the cells. This is the only way to prove that the substance has the desired medical ef- tical industry and subsequent- fect and to identify its side effects. At the Max Planck Insti- ly founded the company Sys- tute for Experimental Medicine in Goettingen, a suitable tasy Bioscience. For this work, integrated measurement process has been developed for the the scientists have now earned first time. The method is able to analyze substances for a third place in the VIP+ inno- multitude of targets in parallel in a single measurement, al- vation awards of the Federal lowing drugs to be developed much faster and more cost- Ministry of Education and Research (BMBF). These honors effectively than with existing methods. The team of re- are awarded to especially successful projects, which are sup- searchers working under Project Leader Moritz Rossner in ported by the Ministry as part of the so-called VIP program

Goettingen refined the method for use in the pharmaceu- to encourage validation. Photos: Kahn/Courtesy of NYU Photo Bureau (top); Kate Kirkby; GSI; private (bottom)

8 MaxPlanckResearch 2 | 19 PERSPECTIVES

A river under human influence

Using the Mississippi as an example, an interdisciplinary project shows how human activity can cause permanent changes in nature

Can the transition into a new geological era dominated by Science. Its participants also include numerous U.S. partners humans also be illustrated at the regional level? That is pre- and the Max Planck Institutes for Chemistry, Biogeochemis- cisely the aim of the project “Mississippi. An Anthropocene try and the Science of Human History. The project is partly River”, which was designed by Haus der Kulturen der Welt sponsored by the German Foreign Office as part of the on (HKW) and the Max Planck Institute for the History of going Year of German-American Friendship in the U.S. The areas around the Mississippi – which was once more of an immense floodplain than a river – evolved into a huge agricultural and industrial corridor as the river was dammed and canalized in the 20th century. Passing through complex, rapidly changing man-made ecosystems, the river acts as the catchment area for a range of cultures and is the scene of historical inequalities. As part of the Mississippi project, scientists, artists, and ac- tivists are working together to develop new methods of research and teaching that transcend the boundaries between disciplines. In collaboration with local initiatives, they are delivering insights into the local dynamics of changes taking place on a global scale.

Changeable: the motif of the Mississippi project is based on a 1940s map documenting historical changes in the riverbed.

On the net

The power of emotions Ethnological research Identifying plants via smartphone Hate and love, disgust and security – emo- in three minutes While out walking, you spot a plant that tions not only move and control us but What does field research look like? you’d like to know more about. What’s also wield immense power over politics What methods do you work with? In the plant called, is it poisonous, or and society, as demonstrated by the exhi- these videos, scientists from the Max might it be a protected species? If you bition The Power of Emotions. Germany Planck Institute for Social Anthropolo- don’t have a plant identification book 19 | 19. The concept was developed by Ute gy in Halle provide an insight into their to hand, your mobile phone will be able Frevert, Director at the Max Planck Insti- work. For example, Imad Alsoos speaks to help in the future – thanks to the app tute for Human Development, together about mobilization strategies of Islam- Flora incognita. This identification soft- with her daughter Bettina Frevert, who ic groups in Palestine and Tunisia, Char- ware was developed with the help of works in historical-political education. lotte Bruckermann presents her field scientists at the Max Planck Institute

The 22 A1-sized posters are intended for research on CO2 emissions trading in for Biogeochemistry in Jena. Flowers display in schools, city halls, libraries, and China, and Brian Campbell gives an out- and leaves can be photographed using other public places. Through individual line of everyday life in the multireli- the smartphone’s camera – and, in a emotions, they explore key events in Ger- gious city of Ceuta, a Spanish enclave in matter of seconds, you receive a sug- man history from the founding of the Wei- Morocco. The charming thing about gestion for the name of the plant as well mar Republic in 1919 to the Peaceful Revo these three-minute videos is that they as further information. The free app, lution of 1989. Among other things, the are not only in English but also in the which is now available in seven lan- website allows users to order the set of mother tongues of the various research- guages, allows plants to be identified posters and offers an overview of where ers – in Arabic, German, and Maltese. by anyone, anywhere. the exhibition is currently being shown. https://www.eth.mpg.de/4811217/ https://floraincognita.com/

Graphic: Meandering Mississippi. Map by Harold N. Fisk, U.S. Army Corps of Engineers, 1944 | Geological Investigation the Al luvial Valley Lower Mississippi River https://machtdergefuehle.de/?lang=en conference_videos ?noredirect=en_US

2 | 19 MaxPlanckResearch 9 VIEWPOINT_Computer Ethics

Digital humanism

From nursing care robots to language assistants such as Alexa and Siri or electronic control systems in your car, digitization is literally drawing closer to our everyday lives. For a long time, the issue of ethics has been on the table in order to keep the use of artificial intelligence within reasonable limits. Our author advocates reviving humanistic ideals for the digital world. His main concern is that people should take center stage.

TEXT JULIAN NIDA-RÜMELIN

or many historians, the greatest innovation cess at its most intense, as well as the continuous in human history is the invention of arable shift from industrial production to service provision farming and livestock farming. The ancient in recent decades, have created a standard of living hunter-gatherer culture that still exists to in the most highly economically developed regions some small degree today was replaced by of the world that has never existed before in the his- settledF farmers and livestock breeders. However, in tory of humankind. Average life expectancy is in- terms of its most important features, the human spe- creasing all the time, even though the way of life of cies was still designed to cope with the old, outmod- the late industrial period is not always conducive to ed way of living. While arable farming and livestock good health. Possibly, digitization will turn out to be the fourth great technological, even disruptive, innovation. Certainly, both its convinced proponents and The big data economy is equally convinced critics alike agree that the human way of life will again be subject to fundamental casting a pall over the beautiful change as a result of digitization. However, the eu- phoric chorus that accompanied the early digital pe- new world of the Internet riod – such as the expectation that with the estab- lishment of the Internet, the age of individual freedom and global democracy would find its high- breeding enabled many more people to live in a cer- est form on the net – is now turning into an anxious tain area than before, at the same time, general health swan song mourning the passing of constitutional deteriorated and epidemics developed, as did myopia, democracy, with electoral manipulation by Cam- tooth decay and flat feet. bridge Analytica and Russian bots. A kind of hang- Industrial technologies played a huge part in over has taken hold. Leading representatives of the shaping our current way of living. The steam engines Internet ideology of anarchic freedom, such as Jaron

of the early industrial period, the electrification pro- Lanier, are revising the assessments for which they Photo: Alamy

10 MaxPlanckResearch 2 | 19 Photo: Alamy appear to be becoming more fluid. more becoming be to appear boundaries the intelligence, artificial of age the In machine? or Human VIEWPOINT_Computer Ethics 2 | MaxPlanckResearch MaxPlanckResearch 19 11 VIEWPOINT_Computer Ethics

became famous decades ago, and which shaped an mathematician Alan Turing). People and other high- entire generation of Silicon Valley employees. The ly developed life forms are not machines. Nature as projection of hippie visions onto the Internet age, a whole is not a machine. Digital humanism does which spread right up to CEO level at Google, Micro not transform people into machines, nor does it in- soft, Amazon and Facebook, now already appears terpret machines as being people. It adheres to the particular nature of human beings and their abilities, and uses digital technologies to expand, rather than to limit them. According to the logic of AI, If people were to act with the same degree of pre- determination as Turing machines, all our behavior there is no freedom of will could in principle be predicted in advance. Since our behavior depends on our convictions, it should in principle also be possible to forecast the convictions to be a thing of the past. The beautiful new world that we will have in the future. However, this would where everyone is connected to everyone else, all mean that we would also be able to forecast the have the same access to information, where dictators knowledge held by future societies, which however cannot survive and the American way of life domi- is incompatible with the genuine progress of knowl- nates the global village, has palled. In the era of the edge and also raises logical problems to which Karl big data economy, commercialization has become all Popper pointed in the past. He argued that the as- too obvious. sumption that all future knowledge can be predicted One feature is now becoming clear that used to on the basis of what we currently know leads to a log- apply to other technological innovations in the past, ical contradiction, since this knowledge is already namely that technologies are always ambivalent; contained in our current knowledge; therefore, there they can be used to both good and bad purpose. is no knowledge in existence that has not yet been There is no mechanism inherent to technology that realized today. However, one precondition of a real guarantees to provide the perfect way of human life. knowledge revolution is that the later knowledge is The assumption that in each case, it is technical not already covered by what is currently known. progress – the development of human productive With this assumption, comprehensive determinism forces and the conversion of natural assets into finds itself in an unresolvable conflict. consumer goods that leads to advances in human According to the logic of AI, there is no freedom history – that can be regarded as the real driver of of will. Machines do what they are programmed to progress, is a Marxist legacy that we should abandon. do. They behave in the way they should. If they People decide on how to use technological options; don’t, this is due to anomalies in the system, in oth- they decide whether digital opportunities contribute er words, random irregularities or damage. Addi- to a humanization of the world and to economic and tionally, some software-controlled systems have social progress, or whether they lead to a loss of po- probabilistic functions, which assign a probability litical control, dependence on the media and the distribution of successor states to a state, rather atomization of society. Digital humanism counters than a fixed successor state. They make it possible both the IT and Internet enthusiasts and the apoca- to construct “learning” robots and more complex lypticists with its message that technical progress is software systems. The transition from determinis- shaped by humans. tic to probabilistic machines not only leads to a sus- From antiquity through to present-day Holly- pension of the categorial difference between human wood, the relationship between human and machine and machine. The alternative is not a choice be- has inspired many myths. Computers are algorith- tween determinism and probabilism, but between mic machines or Turing machines (named after the determination and freedom.

12 MaxPlanckResearch 2 | 19 Humans reflect on their actions, and are in a position would contradict the requirement to observe the rules to tailor their actions to a certain rationale. This abil- of truthfulness and trust. If we were always to be un- ity to make decisions that accord with the best ratio- truthful when this was in our interest, the act of com- nale is what constitutes human freedom and respon- munication would immediately lose its value. sibility, and what separates us from animals and In the same way as overall everyday communica- machines. If the action in question were already de- tion is based on the observance of certain norms and termined every time before any consideration or de- rules, such as truthfulness, trust and reliability, and liberation is made (or even just the distribution of these rules must be generally accepted as general lim- probability of the potential actions), the actor would itations in order to enable us to treat each other hu- not be free, and also not responsible. In fact, strictly manely, it is also true of the Internet that communi- speaking, there wouldn’t be an actor at all. Then there cation is eroded without functioning ethos norms. At would not be an action, but simply pure behavior. times, the anonymity of Internet communication, Another topic that is frequently the subject of dis- the lack of a face-to-face situation and the possibili- cussion in the Internet era is “virtual communication”. ty of communicating under a false name enable ma- However, the term is misleading, since in the so-called nipulative practices that fail to conform to the rules “virtual world”, communication is generally real. of truth, trust and reliability. Every item of communication uses different media. Fortunately, the practice of targeted deception can The oldest medium came in the form of signs and only function on a parasitic basis, in other words, soundwaves, while later cultural techniques such as only when the majority of the communication part- reading and writing used lettering as a medium, and ners adhere to the rules of truth, trust and reliability. the invention of the printing press at the dawn of the It appears that this is still the case. Most social media modern age made this medium available to the mass population. In contrast to what some postmodern theoreticians say, digitization will not bring about an end to the rationality of the Gutenberg era, neither will a Access to the World Wide Web new world of images be created without a logical structure; to a far greater extent, the medial spectrum of should be a basic human right acts of communication will be expanded by a further dimension. There is nothing virtual about this. However, the same rules apply for communication groups, whether closed or open, are noticeably char- on the Internet as for communication in general. acterized by honesty, stability and reliability. An in- Philosophers of language agree that successful commu- dication of this is the positively excessive use of rules nication practice is only made possible when those of behavior and the rigid sanctioning of shitstorms involved in the communication stick to certain con- and individual expressions of displeasure. When few- stitutive rules. These include the rule of truthfulness. er legally sanctioned norms apply, cultural practice This requires that if I make a claim, I am also con- takes on greater importance. vinced that it is true. Equally, we can expect our com- For many people throughout the world today, munication partners to trust us, in other words, that sending e-mails, presenting themselves on the Inter- they assume that the claims that I make are in line net, communicating and accessing all kinds of infor- with my own convictions. These rules are only trivial mation is a part of everyday life. However, not ev- on the surface. After all, they subject the communica- eryone has the same access to the Internet everywhere tion partners to the obligation to orient themselves on in the world. This is known as the digital divide, or what they regard as good rationale in the way they ex- the gap between so-called “onliners” and “offliners”. press themselves, rather than on their own individu- Even if the number of offliners is declining year

Photo: Alamy al interests. In many cases, purely individual interests by year, there are plenty of reasons why access to the

2 | 19 MaxPlanckResearch 13 Internet should be declared a basic human right – consequence of this is that digital immigrants teach today and certainly in the future. The basic under- digital natives a language that they have painstaking- lying principle of human rights has not changed: ly learned, while the pupils, who have learned it the right to self-esteem is inviolable. This is the core since childhood, can speak it with ease. of human dignity, as expressed for example in the In the case of digital technologies, products are ethics of Immanuel Kant or, in the present day, in also changing so fast that knowledge of how to use the ethics of Avishai Margalit in systemic form. The them must constantly be updated, making it not par- conditions of human society change with the times and cultures, however. The definition of exclusion and discrimination practices is not set in stone, but depends on cultural and economic conditions. Hu- The ability to make independent man rights apply in traditional cultures as well as modern ones, although a general education guaran- judgments – a humanistic ideal – teed by the state only recently became a human right in the modern age, since the conditions for is becoming more important this were not provided in traditional societies. Par- ticipation in communication, the free expression of opinion and information freedom are a human ticularly suitable as school learning material. If the right; the media of communication and information characterization of Wilhelm von Humboldt still ap- change with the times. plies today, i.e. that school knowledge is of a canon- The more digital technologies are used in every- ical nature – in contrast to scientific, research- day life, the louder the call will become for digital oriented knowledge – then practicing how to handle education. For example, in 2014, the head of stud- digital end devices cannot be classified as a useful ies of the International Conference of the Learning classroom subject. What, therefore, could digital Sciences, Birgit Eickelmann, complained in an inter- education be like? view with the Frankfurter Allgemeine Zeitung news- Digitalization changes the availability and ar- paper that too many children are not able to work in- chiving of data stocks. Broad areas of the human- dependently on the computer, to create presentations ities, historical and philosophical research (sources, and documents, and that for this reason, we “in Ger- texts, interpretations) are becoming generally avail- many have lost access internationally in many areas.” able to an increasing degree. Today, research and She demanded better digital education, which in gen- travel that used to take up so much time, as well as eral means teaching media skills and how to handle hours spent in specialist libraries, is often no longer the new technologies. With this in mind, in 2016, required. The full digitization of museum stocks cur- the German Federal Ministry of Education started the rently in progress, along with mandatory digital “Education campaign for the digital knowledge soci- documentation in the sciences, will further improve ety”, which is designed to promote learning with dig- this situation. Since the amount of time and mon- ital media and the teaching of digital skills. The aim ey involved in acquiring data is decreasing, this form is to make increasing use of new learning apps, vir- of accumulated knowledge is losing value. As a re- tual libraries and virtual reality glasses in classrooms, sult, methodological skills are becoming more im- lecture theaters and companies. portant than data skills. This is already reflected in However, the problem with these forms of digi- study programs, where entire areas of knowledge are tal education campaign is that their goals remain too regarded as non-essential and are being replaced by vague, and they focus only on the ability to handle methodology training. technologies, something that is already taken for As a result of the digitization of data provision,

granted by the younger generations. The grotesque numerous “gatekeepers” such as librarians, publish- Photo: Alamy

14 MaxPlanckResearch 2 | 19 VIEWPOINT_Computer Ethics

ing editors, journal reviewers, and newspaper, TV or radio editorial boards are no longer required. This means that there is an increasing demand for the ability to make an independent judgment. Data provision does not replace the ability to evaluate and examine data as to whether it is reliable and what arguments can be based on it. The World Wide Web is confronting us with a far greater variety of interpretations, theses, theo- ries and ideologies, making it more difficult to form an opinion. As a result, the old humanistic education ideal formulated in Plato’s Theaitetos dialog 2,500 years ago, which places the independent power of judgment, the ability for theoretical and practical common sense at the forefront, has gained THE AUTHOR enormously in value. People who tend to follow suggestively formulated convictions, or who screen Julian Nida-Rümelin teaches philosophy and political themselves off from unpalatable facts, quickly lose theory at the Ludwig-Maximilians-Universität in their bearings in the new, digital data universe. Munich. He is responsible for the field of culture at the They enclose themselves in “bubbles”, such as those Zentrum Digitalisierung.Bayern, and is a member of provided by the social media in particular, or they the Board of Directors of the newly-founded Bavarian lurch about through the data world, pulled in dif- Research Institute for Digital Transformation. ferent directions by different influences. As a consequence of digitization, we are not living in a knowledge society, but rather in a data society, or better, in a data economy. THE BOOK Ultimately, many aspects of digitalization point to a further key goal of humanism, namely the for- Julian Nida-Rümelin mation of personality. Today, this topic is of greater Nathalie Weidenfeld importance than ever before, and its significance will Digitaler Humanismus further increase as our methods of communication Eine Ethik für das Zeitalter der become digitized and during the course of interac- Künstlichen Intelligenz tions, transfers of data and services and digitalized Piper Verlag, Munich 2018 production (key word: Industry 4.0). The reason for Hardback, 224 pages, EUR 24 this is quite simple: the more varied, volatile and complex personal connections, community net- works and ways of living become, the greater the need for the individual ability to be the author of one’s own decisions, convictions and projects. Digi- tal opportunities create new personal freedoms and trigger an enormous impetus for change, both culturally and economically. They therefore also strengthen the potential for autonomy among individuals, while at the same time exposing them to the

Photo: Alamy Photo: Andreas Müller stress of an increasing need for orientation.

2 | 19 MaxPlanckResearch 15 Post from the Antarctic

McMurdo Station Antarctic

A paradise in white and blue

Max Planck scientists cooperate with partners in around 120 countries all over the world. Here they write about their personal experiences and impressions. Konrad Meister from the Max Planck Institute for Polymer Research in Mainz spent four months in the Antarctic conducting research in cooperation with the Universities of Oregon and Illinois (U.S.). He tells of long working days, explains the connection between his research and ice cream, and why the Antarctic is a place full of contradictions.

It was the moment when the first fish took the bait and I thought, “That can’t be true. All around you, there’s nothing but ice and snow. And you‘re sitting there, fishing,” that I realized that now I really was in the Antarctic. The southernmost continent on Earth, and 16,796 kilometers away from Mainz. I had undertaken an arduous journey to get here. From Frankfurt, the first stop was Christchurch in New Zealand. From there, I flew with an LC-130 U.S. Air Force plane to the Antarctic, to the McMurdo Station, an old navy base which at certain times of the year houses several hundred scientists, depending on the season. I can best describe everyday life there as “eat, sleep, science.” Since it never gets dark, it’s by no means unusual to work from 8 in the morning until 11 at night. The daily routine is pretty much the same: load up the PistenBully, drive to the fishing spot, and drill a hole through the ice, which is several meters thick. Then the first task is to catch fish! Once my colleagues and I have caught enough fish, we drive back to the station. There, we take a small amount of blood from the fish and place them in special aquaria in order to prepare further tests. The focus of my research is on why fish don’t freeze in the Antarctic. The American Arthur DeVries is considered a pioneer in this field. In the 1960s, he discovered that these fish have special pro-

teins that act as a type of natural anti-freeze, which is why DeVries called them anti-freeze pro- Graphic: iStockphoto

16 MaxPlanckResearch 2 | 19 Dr. Konrad Meister , 36, studied biochemistry at the Ruhr-Universität Bochum and gained his doctorate in physical chemistry. Following a stint as a postdoc at the AMOLF research Institute in Amsterdam, supported by a Marie- Curie scholarship, he has been a Group Leader at the Max Planck Institute for Polymer Research in Mainz since summer 2018 . In his work, he focuses on proteins with unusual properties.

teins. Since then, quite a lot has been learned about how they function. If a fish absorbs small ice crystals, anti-freeze proteins dock onto them and prevent the ice from further increasing in size. Here, I am particularly interested in the molecular mechanisms. How do these proteins bond with the ice crystals? Do they change their structure during the process? For this reason, I moved to the Department for Molecular Spectroscopy at the Max Planck Insti- tute for Molecular Research, which with its state of the art spectroscopy methods and outstanding ice laboratory offers ideal conditions for my research. Now the only thing that was missing were the proteins, and I am grateful that Director Mischa Bonn gave permission for me to go on this expedition for several months. One important area of application for my research is cryopreservation, with the aim of freezing organs and other tissue. However, anti-freeze proteins are also used in the food industry, where they ensure, for example, that ice cream stays creamy. They are also of interest as a very powerful anti-freeze for a large number of industrial surfaces, such as the blades of large wind turbines. The Antarctic is a place full of contradictions: the endless expanse of the ice often gave me a feeling of boundless freedom, while at the same time, you are a prisoner on this continent and are reliant on the base station. Although the Antarctic is one of the most remote regions in the world, you are constantly surrounded by people at the station. There isn’t any such thing as your own private space. Also, life in the Antarctic is very monotonous. For a start, there’s the everyday fishing expeditions; then there’s the constant brightness and the fact that you can hardly smell or hear anything. Also, I spent months on end living with the same people, who are also all approximately the same age. Under those conditions, you long to see someone different once in a while. However, there are some routines that I never tired of. Who wouldn’t love to see whales, seals or penguins right up close on a regular basis? And with time, I began to pick out increasingly subtle differences in the landscape, which at first sight seems to consist of nothing but ice and snow. For

Graphic: iStockphoto Photo: private that reason, I will always remember the Antarctic as a special place: a paradise in white and blue.

2 | 19 MaxPlanckResearch 17 the current and voltage between the poles. the between voltage and current the of measurements taking times, multiple systems test the discharge and charge they this, Todo materials. raw renewable from made electrolyte an or electrodes example, for with, work cells the well how test to potentiostat a use Potsdam in researchers components: battery sustainable Testing

Photo: Bettina Ausserhofer Photo: Bettina Ausserhofer of the biobattery the of beginnings The in Potsdam. in ColloidsInstitute of and Interfaces work by work of focus the is Thispossible. as sustainable and non-toxic as are that materials of made be should which capacitors, and batteries powerful on relies supply short in is it when times for panels solar and turbines wind from power surplus store to ability The problem. storage a has future the of supply energy The TEXT KARL HÜBNER KARL Clemens Liedel and Liedel Clemens at the the at Oschatz Martin Max Planck Planck Max 2 | MaxPlanckResearch 19MaxPlanckResearch

FOCUS_Energy

19 FOCUS_Energy

O O HO O OH OH NH2 n - + O O -2e , -2H O O HO O - + HO O NH +2e , +2H NH nn O HO O OH O HO O

A recipe for an organic cathode: Max Planck chemists combine chitosan from shrimp shells with vanillin, the aroma of vanilla, which can also be produced from wood. By doing so, they hope to be able to replace substances such as lithium cobalt oxide, which is currently used for the cathodes in lithium batteries and whose use is questionable for political and environmental reasons.

here’s a hint of vanilla in the pointment. There are no baked goods all: ideally, the new battery materials air. It’s not necessarily what anywhere to be seen. In Liedel’s lab, should be made from renewable raw you expect to encounter in a vanillin is currently being used as a materials and thus ensure almost un- chemistry lab, let alone in starting material for a potential elec- limited availability. That is certainly one used for research in the trode material of the future. not the case with today’s lithium bat- field T of battery materials. “That’s from Clemens Liedel is a researcher at the teries. Lithium itself is quite a rare the vanillin,” smiles Clemens Liedel. Max Planck Institute of Colloids and metal and is found in only a limited But anyone looking forward to some Interfaces in Potsdam, where he leads number of deposits around the world. leftover Christmas cookies or freshly the “Sustainable Energy Storage Mate- Some two-thirds of lithium batteries baked birthday cake is in for a disap- rials” working group. The name says it also contain cobalt, a metal whose extraction is often accompanied by social and environmental problems in the ex- porting countries. Other components include electrolytes, which are sometimes toxic or even flammable. Given the rapidly rising demand for storage capacity, these conditions are still anything but ideal. Clemens Liedel believes that the approach using vanillin could offer a significantly more sustainable alternative, as this substance can be prepared from one of the most common materials of all – from lignin, a principal component of wood. Every year, nature produces many billions of tonnes of lignin. But how can an organic molecule be used as a material for batteries? After all,

A good mixture: working in glass flasks, the Potsdam-based chemists convert chitosan and vanillin into a sustainable

electrode material. Photos: istockphoto, shutterstock, Bettina Ausserhofer (from top to bottom); graphic: MPI of Colloids and Interfaces

20 MaxPlanckResearch 2 | 19 when it comes to batteries, we typical- from the shells of shrimp, for example. Getting an overview: to investigate the ly think of metals such as lead, cadmi- Soot is still obtained from petrochem- properties of sustainable electrode materials, um, or indeed lithium. “In very gener- ical resources, but could also be pro- the researchers apply them to microscope slides with carbon paper. al terms, what you need are substances duced from biomass. At present, the that can release electrons and then ab- Potsdam-based researchers are testing sorb them again,” explains Liedel. a pure vanillin/carbon mixture that charging cycles.” That, of course, is an “These might be metals, which are then works without a binder or chitosan, essential prerequisite for rechargeable converted into metal ions, but they can provided the vanillin first undergoes a batteries – and the researchers say that also be organic substances.” chemical modification. the latest vanillin-based approach has Specifically, the researchers in Pots- already proven successful. dam envisage using vanillin for the A MORE SUSTAINABLE SOLUTION However, Clemens Liedel’s group is cathode – that is, for the positive pole FOR ELECTROLYTES also putting a great deal of thought into of lithium batteries – instead of sub- future electrolytes. The electrolyte is stances containing heavy metals, such To test the electrode material, a mem- the component in a battery that con- as lithium cobalt oxide. But that’s eas- ber of the team applies an extremely tains the mobile charge carriers (the ier said than done – a brittle powder thin layer of the mixture of substances ions), which are responsible for balanc- like oxidized vanillin cannot readily be to a sheet of carbon paper, from which ing out the electrical charge between used as an electrode material. “Normal- they punch out a small, circular section. the two poles. Electrolytes usually con- ly, you mix the substance with a bind- This is then inserted into a plastic hous- sist of a conductive salt that is adapted ing agent to create a compact paste and ing, followed by a separating mem- to the electrodes, as well as a solvent. make it conductive by adding carbon,” brane, an electrolyte, and a counter “Currently, these are typically solutions explains Liedel. Although this ap- electrode – and the battery is complete. of toxic lithium salts in flammable or- proach proved successful, it was not It is now possible to measure the bat- ganic carbonates,” explains Liedel. But sustainable enough for the chemist – he tery’s voltage between two stainless- the chemist has a more sustainable – was still concerned about the binder, a steel cylinders protruding from the and safer – solution in mind. fluorinated polymer. plastic housing. Today, it is 3.1 volts. Here, too, the team has enjoyed At present, therefore, the research- But that’s not the only thing the some initial successes. Clemens Liedel ers in Potsdam chemically bond their scientists test. “In addition, we always walks into another of his labs, reaches vanillin to the biobased polymer chi- carry out long-term tests involving a for a round-bottomed flask, and briefly tosan before mixing the combined series of alternating charging and dis- swirls it around in the air. A colorless substance with particles of soot – com- charging processes,” says Liedel. “In mixture can be seen sloshing around pletely without binders. Chitosan is a this way, we can see whether our elec- inside. “That’s an ionic liquid,” says

Photos: istockphoto, shutterstock, Bettina Ausserhofer (from top to bottom); graphic: MPI of Colloids and Interfaces Photo: Bettina Ausserhofer sugar-like polymer that can be obtained trode is actually suitable for frequent Liedel. The term is used to describe salts

2 | 19 MaxPlanckResearch 21 22 fore offerexcellentfireresistance.” ic liquidsarebarelyvolatileandthere- ing good conductors of other ions, ion- solvents forelectrolytes:“Aswellasbe- this groupofsubstancesmakesgood anions. The researcher explains why charged cationsandnegatively the liquidismadeupofpositively 100 degrees centigrade. Like all salts, that areliquidattemperaturesbelow FOCUS_Energy only the porous carbon material remains ( remains material carbon porous the only that so mold silica the away etch researchers l pores contains which carbon, into sugar the converts air of absence the in this Heating salt. and sugar materials starting the of solution aqueous concentrated highly a with (silica, quartz of made mold a fill chemists powerfulsupercapacitors, thePotsdam-based for material a create to battery: storage Baked 3 2 1 e ft behind by the evaporating salt ( salt evaporating the by behind ft Por mold the in Car s Silica mold with MaxPlanckResearch 2 MaxPlanckResearch tarting materials materials tarting ous carbon bon material bon

| 19 2 ). The The ). 3 1

). ) with theionicliquid, chitosan bining theorganiccathode material er,” saysLiedel–inotherwords, com- bringing alloftheseapproaches togeth step. “We now wanttoexperimentwith group is now looking to the next big components,the individual battery the pores,”saysLiedel. in particularmigratereadilythrough portedly beensuccessful.“Theanions periments withthismaterialhavere- macromolecules withsmallpores.Ex- tional substancestocreateanetworkof up thechitosanchainsbyaddingaddi- chitosan. Theresearchers simplylinked accident duringtheirworkinvolving which they stumbled across entirely by can alreadyofferanalternative–one ing charged.Heretoo,Liedel’s group isbe electrical loadorwhilethebattery tive to the positive pole through an when electrons migrate from the nega- charge balancing,whichisnecessary ions of the electrolyte in order to allow based plasticandispermeabletothe separator istypicallymadeofanoil- avoid anelectricalshort-circuit. This arated byafine-poredmembraneto closetogetherandsep- are usuallyvery In commercial batteries,thetwopoles BATTERY COMPONENTS A MARRIAGE BETWEEN materials arealreadyrenewable. ionic liquidforwhichhalfoftheraw His grouphasnowidentifiedasuitable ture rangeinwhichtheyareliquids. of themolecules,butalsotempera- configure notonlytheionconductivity For example,researchers canreadily fine-tune theirchemicalproperties.” another importantfeature:“It’s easyto materials. ForLiedel,theyalsohave fore bederivedfromrenewableraw purely organic and, ideally, can there- Moreover, someionicliquidsarealso After extensivebasicresearch into - - ity ProgrambytheGermanResearch demonstrated by the launch of a Prior- ing andsustainablealternativeisalso materials arecurrentlyseenasapromis material, suchasoxidizedvanillin. ionic liquidiswithabiobasedelectrode tion ishow chemically compatible the few details to clear up.” One such ques- sium-based anode.“Butwestillhavea membrane, andasodium-ormagne- These are typically released by a metal, These aretypicallyreleasedby ametal, the anodethatsupplies electrons. proving thespecificenergyof anodes. This wouldalsobeinstrumental inim- ber ofbindingsitesformetal atoms. surface area with the maximum num aim istoprovidethelargestpossible a preciselydefinedsize.Inprinciple,the with carbonmaterialsfeaturingporesof storage batteries. Oschatzexperiments cluding the use of such materials in terials,” which studies applications in- mental Utilization of Carbon Nanoma- working groupon“EnergyandEnviron those ofLiedel’s team.Heleadsthe laboratories justafewstepsawayfrom Liedel’s attheInstitute.Oschatzhashis on thisisMartinOschatz,acolleagueof can beputtopracticaluse. tions must still be resolved before they sustainable, anumberof technical ques- better availability, as well as being more cussed andwouldoffersignificantly or magnesiumarealreadybeingdis- Although othermetalssuchassodium a combinationoflithiumandgraphite. At present,thisanodeusuallycomprises materials research is thenegativepole. for whichLiedeldoesn’t dohisown includes ClemensLiedel’s group. sponding research networkthatalso a total of EUR 12 million for a corre- a six-yearperiod,theDFGwillprovide Foundation (DFG)inApril2019.Over The fact that polymer-based battery The fact that polymer-based battery While a battery is discharging,itis While abattery Another oftheresearchers working So far, component theonlybattery - -

Graphic: MPI of Colloids and Interfaces which then becomes a positively charged trons released by the sodium during the ion – that is, a cation. The simplest discharging process. Echoing Liedel’s thing would therefore be to make the approach with his organic cathode electrodes from that metal, but that is materials, Oschatz therefore had to hard to do with certain metals. Lithium combine his polymer with soot in or- is therefore usually combined with der to obtain a suitable electrode ma- graphite, intercalating the lithium atoms terial. Specifically, the researchers in between the graphene layers. Potsdam do this by coating extremely thin carbon threads with their carbon/ POROUS CARBON FOR nitrogen polymer. Following initial test- SUPERCAPACITORS ing, Oschatz says that the storage capacity of their material is already relatively Martin Oschatz is working on a similar good for sodium. solution for sodium. “The method in- Unlike Liedel, however, Oschatz volving intercalation in graphite doesn’t doesn’t just have batteries in his sights. work with sodium,” he says. But the car- The porous, nitrogen-rich carbon poly- bon chemist has already found another mer has apparently also proven to be Top No superficial matter: Milena Perovic solution in the form of a carbon-based an effective catalyst material for the en- and Martin Oschatz prepare for a polymer with two important special fea- ergy-efficient synthesis of ammonia. measuring procedure that allows them tures: the flat macromolecule forms With regard to other environmental ap- to determine the surface area of carbon materials. The device determines how sieve-like pores of its own accord, and plications, Oschatz says that, because much gas can be absorbed by four samples the chemists have carefully selected the the pores are good at capturing carbon held in cooling vessels. parent compounds in order to incorpo- dioxide molecules in particular, the ma- Above A tidy job: before the surface area rate nitrogen atoms at the edge of the terial also makes an effective CO2 filter is measured, the samples are heated in pores. “These ensure the stable storage for processes such as flue gas scrubbing. a vacuum to remove volatile substances of metal atoms,” Oschatz explains. Even in terms of electricity storage, that would distort the analysis results. However, the researchers first had biobatteries are not the only application another obstacle to overcome. Although that the chemist envisages. Oschatz the high nitrogen content increases also wants to use highly porous carbon the binding strength for sodium, it also as an electrode material in supercapac-

Graphic: MPI of Colloids and Interfaces Photos: Bettina Ausserhofer (2) reduces the conductivity for the elec- itors, which provide very fast access to

2 | 19 MaxPlanckResearch 23 Food for thought: Clemens Liedel and Martin Oschatz discuss new ideas with a view to developing more sustainable materials for energy storage devices. the energy they store. In addition, ca- facturing process, the porosity of acti- garage: “We need lots of streets that pacitors generally have a much longer vated carbon is quite random and com- serve as access roads, which need to service life than batteries, although the pletely disordered,” says the chemist. be lined with a sufficient number of amount of energy they can store was He wants a material whose surface parking bays.” also much smaller until now. Super structure is clearly defined down to the To build these nanoscale parking capacitors are already found in appli- nanometer level – that is, to within a garages, Martin Oschatz’s team first cations where large quantities of elec- few millionths of a millimeter. More- uses a special silicate material to create tricity are required at short notice – for over, this structure should ensure that, a sort of tiny baking tin with cavities example, when starting up a streetcar. when a voltage is applied, the material precisely matching the desired struc- Some automobiles also use supercapaci- can adsorb and release as many ions as ture of the parking garage. The model tors for energy recovery during braking. possible, as quickly as possible. essentially consists of countless paral- The capacitors that Martin Oschatz lel tubes separated from one another deals with store electrical energy in the A PARKING GARAGE FOR IONS by a gap of a few nanometers. The re- form of an electric field – that is, by searchers fill the baking tins with a loading up two electrodes with oppo- Martin Oschatz therefore uses an al- mixture of sugar and salt and then put site charges. To balance out the charge, most pure carbon material with a large the whole thing in the oven at about oppositely charged ions from an elec- surface area and an ingenious pore 800 degrees centigrade. trolyte accumulate at the respective structure. This proves to be a particular- In the absence of air, the sugar is py- electrodes. How much charge a capaci- ly effective electrode material for ener- rolyzed to leave behind a carbon mate- tor stores, and how quickly it charges gy storage devices. The material can rial, whereas the salt evaporates in the or discharges, depends on how many bind to many more ions – and release oven to leave behind cavities – that is, ions the electrodes adsorb and release them again – faster than the nitro- the parking bays for the ions. By vary- and how quickly they can do so. gen-containing carbon that Oschatz’s ing the quantity of salt, the chemists The activated carbon typically used group developed for sodium batteries. can control the pore size and create in many current supercapacitors al- The reason why the electrode ma- parking spaces with dimensions in the ready has plenty of contact with the terial is so effective is that it has enough order of one nanometer or less. The re- outside world, providing a specific sur- pores along its contact surfaces with searchers then chemically dissolve the face area of around 1,500 square meters the electrolyte to adsorb ions without baking tin, leaving behind a vast num- per gram. But Oschatz wasn’t going to subsequently blocking others. Oschatz ber of carbon rods connected to one

settle for that. “Because of the manu- likes to think of it as a sort of parking another by small bridges. “The empty Photo: Bettina Ausserhofer

24 MaxPlanckResearch 2 | 19 FOCUS_Energy

spaces between the rods are then our tainable than, say, lithium or cobalt.” Antonietti also has another vision: “At streets,” says Oschatz. It is through He believes that the environment also some point, every household will need these streets that the ions reach their stands to benefit from the development a storage battery of its own, and each parking spaces. of materials with especially high specif- summer they’ll charge it up with the ic energy and long service lives. energy they need for the next winter.” LOWER COSTS PER Markus Antonietti is also enthusi- This would involve quantities of ener- STORED KILOWATT HOUR astic about the results obtained so far. gy that simply couldn’t be stored sus- He leads the Department of Colloid tainably with today’s batteries. “We With this specially designed porous Chemistry – where Clemens Liedel and therefore need materials that are free of structure, the researchers can now Martin Oschatz are also researchers – metals – and ideally renewable,” says achieve specific surface areas of up to at the Max Planck Institute of Colloids Antonietti. He’s therefore also pleased 3,000 square meters per gram – the and Interfaces in Potsdam. Antonietti to detect a hint of vanilla drifting over equivalent of half a football field in a believes that the new materials for su- from Liedel’s labs from time to time. Of few granules of carbon. To determine percapacitors will one day pave the course, future users of these storage bat- the surface area, they use an instru- way for a significant reduction in the teries wouldn’t get the chance to enjoy ment that measures how many parti- cost per stored kilowatt hour of elec- this aroma. Once incorporated into a cles of a gas bind to a specific quanti- tricity. In his view, the objective must battery, the vanillin would be chemical- ty of their materials. From this, they now be to boost the storage capacity ly bound – and therefore odorless. can derive the specific surface area of to the extent that these energy storage their substances. devices might one day take on the role www.mpg.de/podcasts/energie Of course, they have already taken of existing batteries. (in German) measurements to determine how quick-

ly their material charges and discharg- . es again. “We’ve had some samples that we could charge and discharge ten SUMMARY

times faster than activated carbon,” l Current battery systems are based on raw materials that are incompatible says Oschatz, adding that the storage with the sustainable expansion of storage capacities.

capacity also exceeded that of previous l Max Planck researchers are therefore investigating battery components – such electrode materials. as electrodes, electrolytes, or separators – made from renewable raw materials Sebastian Pohlmann is also observ- like vanillin, chitosan, and appropriate ionic liquids. ing these attempts with interest. Pohl- l They are also attempting to increase the specific energy and charging and mann is in charge of material and cell discharging speed of supercapacitors by developing corresponding electrode materials with a larger surface area and a structure that is as precisely development at Skeleton Technologies, defined as possible. the only manufacturer of supercapac itors in Europe, and is working on electrodes with improved properties at the GLOSSARY company’s Grossroehrsdorf location. “In this context, it’s very important to Anode: Together with the cathode, this is one of the electrodes at which electrical bring greater order to the structure of energy is stored as chemical energy and converted back into electrical energy within a battery or an electrolytic or fuel cell. When a battery is discharged, anions – that is, the porosity,” he says. negatively charged particles from the electrolytes – or neutral metal atoms of the And what about sustainability? On electrode material release electrons, which flow to the cathode via an external circuit. first inspection, sucrose – one of the es- Electrolyte: The conductive medium between two electrodes. It contains ions that sential starting materials – appears to ensure the flow of current between the electrodes and that are also involved in the offer a similar degree of renewability electrochemical processes taking place at the electrodes, such as in batteries. to the lignin that Clemens Liedel used to Cathode: This takes up electrons from the external circuit and transfers them to the elec- prepare vanillin. “Of course, sucrose is trolyte. It is where metal cations, for example, are converted into uncharged metal atoms. a foodstuff first and foremost,” Oschatz Separator: A membrane, usually made of a porous plastic, that separates the anode admits, but he is keen to emphasize and cathode compartments. It prevents short-circuiting between the two electrodes but is permeable to ions so that a current can flow through the electrolyte. that, “as a raw material for electrodes,

Photo: Bettina Ausserhofer the substance is still much more sus-

2 | 19 MaxPlanckResearch 25 pipework, nozzles, and gangways. and nozzles, pipework, Wendelsteinof chamber plasma the technology: of labyrinth A FOCUS_Energy -X sits deep within a maze of maze a within deep sits 7-X

Photo: Jan Michael Hosan/IPP Photo: Jan Michael Hosan/IPP stellarator Solarinthe fire for Plasma Physics approach to this form of energy generation. energy of form this to approach energy. At the Wendelstein the At energy. of source new completely a represent would and Earth on power sun’s the recreate to aimsfusion Nuclear by by ring toisthering-shapedcenterpiece titude ofover250pipeconnections of us. The ring is hidden within a mul shedinfront filling theseveral-story of the gigantic 725-tonne metal object Y TEXT Thomas KlingerThomas ROLANDWENGENMAYR the plasmaphysicistisrefer- stein 7-X.The“torus”that WendelHirsch ashesurveys torus itself,”saysMatthias ou can barely make out the ,

in Director at the the at Director Greifswald, 7 -X facility, researchers led led facility, researchers -X - - are exploring one one exploring are this labyrinth–althoughthere’s one and Hirschisexpertlyguiding usthrough for PlasmaPhysics(IPP)inGreifswald, and equipmentcupboards. interspersed withpipelines,cablestrands, staircases, balconies, and access bridges surrounded byscaffoldingmadeupof for the lay person. In turn, all of this is and nozzles–atrulybewilderingsight Max Planck Institute Max We’re at the Max Planck Institute 2 | MaxPlanckResearch 19MaxPlanckResearch

27 FOCUS_Energy

piece of equipment whose purpose they experience unimaginable pres- charged, they can be confined by a even he can’t fathom. You can’t blame sures of some 200 billion atmospheres, strong magnetic field. This acts like a him. After all, we’re climbing through which no solid material could even virtual thermos flask and is the trick on the external scaffolding of an enor- come close to withstanding here on which fusion research relies. mously complex machine that is now Earth. Exploiting solar energy in this In a future fusion power plant, the used for research by over 200 scientists way therefore seemed like an unattain- plasma vessel would only contain from across Europe, Australia, Japan, able dream – until ingenious physicists about one gram of the helium/tritium and the U.S. Even for an expert like came up with an alternative. In the mixture. This almost non-existent Hirsch, it’s impossible to get to grips mid-20th century, they discovered that quantity of fuel could produce 90,000 with every last detail. nuclei of the heavy hydrogen isotope kilowatt hours of thermal energy – Researchers from Germany – and deuterium, which contains a neutron equivalent to the heat of combustion above all from the Max Planck Society – in addition to its proton, and tritium, a of 11 tonnes of coal. However, burning have taken a leading role in the con- superheavy hydrogen isotope with two that amount of coal would release over struction of Wendelstein 7-X. The neutrons, can also fuse to form helium. 30 tonnes of carbon dioxide into the at- project aims to support an important mosphere. By contrast, fusion power scientific objective: harnessing the so- NUCLEAR FUSION – A NEW FORM plants would operate on a carbon-neu- lar fire as an almost inexhaustible OF ENERGY GENERATION tral basis. This, together with their ex- source of energy for applications such tremely low fuel consumption, is what as power generation. Deep within the This fusion reaction takes place in an makes them such a promising idea in a sun, temperatures of 15 million degrees extremely thin, hot gas, and is easier to century in which our lives will increas- cause hydrogen nuclei – protons – to implement from a technical perspective ingly be shaped by climate change. fuse, forming nuclei of the element he- due to the low pressures involved. That The prospect of developing a climate- lium and releasing vast quantities of being said, it also requires temperatures friendly source of energy may well be energy in the process. Without this fur- even higher than those present in the the reason why Robert Habeck, co- nace running on solar fusion, Earth sun – well in excess of 100 million de- leader of Alliance 90/The Greens, ex- would be a cold, dead planet. grees. In a high-temperature plasma of pressed his positive attitude to the re- However, the light hydrogen atoms this kind, electrons and atomic nuclei search during a recent visit to Wendel- only fuse when exposed to the crushing are completely separated from one an- stein 7-X. When the foundation stone gravitational force of the sun. There, other. As both of them are electrically for the facility was laid in 1997, his party’s supporters protested against it. “Today, we take a less ideological line on nuclear fusion,” Habeck explained. THE ROAD TO NUCLEAR FUSION In his view, the basic research is fascinating and should be promoted. “Ex- The fusion of deuterium and tritium to form helium ought to be performed in a ploring alternative energy supplies is very thin, hot plasma. Even with a relatively small number of collisions, the heavy fundamentally the right thing to do.” hydrogen nuclei release sufficient energy to maintain the fusion reaction. Thomas Klinger points out that fu- Although any fusion plant of the future will therefore constitute a nuclear facility, sion energy is the only new form of pri- it also offers some key advantages over today’s nuclear power stations. In the mary power generation that humanity event of an accident, there is no risk of a core meltdown, as the sensitive plasma is currently researching: “It’s the last simply goes out. The radioactive tritium is also bred and consumed directly with- unopened barrel of energy, so to speak.” in the self-contained fusion power plant. Moreover, as only a few grams of fuel are As if to highlight this statement, a burst needed, there are none of the disposal problems associated with nuclear power of warming sunlight illuminates the of- plants. Likewise, fusion doesn’t produce tonnes of radioactive waste that then fice of the Max Plank Director, who need to be stored for many thousands of years. When a plasma vessel is dismantled leads the Greifswald location of the Max at the end of a fusion plant’s useful life, only internal components are radioactive. Planck Institute for Plasma Physics. These must then be stored securely for a few decades – a manageable period of With his wiry build, the physics pro- time for human civilizations. fessor looks as if he might jump up and reach for a wrench at any moment.

28 MaxPlanckResearch 2 | 19 Access for researchers: Matthias Hirsch prepares a nozzle through which the sensors of various analytical devices transmit data about the properties of the plasma.

Indeed, the researcher has temporarily ator using light hydrogen. A stellarator Wendelstein 7-X is currently being found himself in the role of site super- is one of two types of fusion devices that adapted for the next series of measure- visor – and on a very complex construc- are currently being researched. As the ments after completing three previous tion site. Little by little, the Greifswald biggest stellarator experiment to date, series, each of which ran for 15 weeks. researchers need to forge their way into the machine in Greifswald is intended On 10 December 2015, the first plasma uncharted technical territory. to demonstrate that facilities of this kind was fired up to a temperature of one But Wendelstein 7-X itself is not a are fundamentally capable of confining million degrees. It consisted of a thou- nuclear facility and is not designed for a hot plasma for long enough and with sandth of a gram of helium, which was nuclear fusion. Rather, the experiment the requisite efficiency. That, in turn, intended to act as a cleaning agent in is an opportunity for physicists to study would pave the way for a fusion power order to remove contamination from the behavior of a hot plasma in a stellar- plant based on this technical principle. the plasma vessel. This is an important step because hydrogen plasmas are highly sensitive. On 3 February 2016, the researchers in Greifswald then generated a hydrogen plasma for the first time – in the presence of German Chan- cellor Angela Merkel. The plasma can be heated using various techniques. The electrons can be set in motion using a beam of microwave radiation – a high temperature simply means that particles are moving

Construction diagram for a magnetic cage: the plasma (pink) is forced to adopt a convoluted path by 70 magnetic coils threaded together around the chamber. Countless openings in the system’s casing

Photo: Jan Michael Hosan/IPP (top), graphic: IPP (bottom) provide access to the interior.

2 | 19 MaxPlanckResearch 29 around quickly. As the electron soup in The system is currently out of action the plasma mixes with the hydrogen for about two years while the team in nuclei, it also warms them up. In addi- Greifswald installs an active water- tion, the scientists in Greifswald are cooling system. This should allow testing a second heating method that Wendelstein 7-X to cope with plasma involves firing fast-moving hydrogen discharges lasting for half an hour at atoms into the plasma. In the future, very high temperatures. “A water-cool- there are also plans to heat the protons ing system may sound trivial,” says directly using powerful radio waves. Klinger, “but for us it means perform- Wendelstein 7-X has already broken ing plumbing work to an extremely a number of records set by other stellar- high standard.” Every part of the plas- ator-type plasma experiments. These in- ma vessel that is exposed to heat must clude discharges lasting for almost half be connected to the cooling system, a minute with a plasma temperature of and this work will therefore involve a well over 40 million degrees centigrade. total of four kilometers of water pipes. Cooling system and filter: the entire plasma chamber is clad in more or less square- In other low-density discharges, the “It’s a huge branched-water system,” shaped graphite tiles. Much smaller, electrons have reached temperatures of says Klinger. rectangular graphite plates cover the as much as 100 million degrees. This divertor, which runs through the chamber also represented the technical maxi- THE DIVERTOR DRAWS FUSION like a ribbon (large image). Passing through mum at the current stage of comple- its baffle plates are water pipes (small HEAT OUT OF THE PLASMA image) that are intended to carry heat from tion, for the walls of the plasma exper- the plasma to the generators in a fusion iment were not yet actively cooled. As In this regard, one particular challenge power plant. However, the divertor not a result, the interior of Wendelstein 7-X is that a high vacuum must be present only cools the plasma but also contains heated up not only due to radiant heat in the plasma chamber during opera- cooling coils in its wall in order to freeze out impurities. from the plasma but also due to hot par- tion. What the researchers fear most ticles escaping from the magnetic cage are tiny leaks in the water pipes, as and colliding with the vessel wall. After these are very difficult to detect. A longer discharges, the plasma vessel “dripping nose”, as Klinger puts it, therefore had to cool down for about a could be enough to destroy the vacu-

quarter of an hour before the next shot. um by allowing water to evaporate. Photos: Bernhard Ludewig/IPP (top), IPP (bottom)

30 MaxPlanckResearch 2 | 19 FOCUS_Energy

Strict standards therefore apply during er region and the wall. Charged impu- for plasma confinement. In total, 70 of the modification work. rities force plasma electrons to change these coils are strung together around However, the greatest technical de- their trajectories, leading to the emis- the plasma chamber like bracelets on a mands must be met by the divertor. sion of X-rays. Moreover, the impurities wrist. Most of the coils have a convo- This sits on the inner wall of the ring themselves are excited by the collisions luted geometry and therefore generate and consists of a series of consecutive with plasma particles, resulting in a magnetic field with multiple twists high-tech plates that protrude into the greater radiative energy losses from and turns. This field acts on the hydro- edge of the hot plasma during opera- thin plasma, which experiences signif- gen nuclei and electrons as they speed tion. Accordingly, the plates must be icant cooling due to these two effects. past, forcing as many as possible onto able to withstand extremely high tem- magnetic roller coasters that repeated- peratures. In a future power plant, the THE CONSTRUCTION PROCESS – ly hurl them back into the hot plasma. plan is for similar plates to extract a A GIGANTIC 3D PUZZLE After all, the aim is to minimize the proportion of the fusion heat from the number of hot particles that escape. plasma. This will then drive steam tur- Moreover, the divertor helps to keep the The individually shaped coils were bines by heating water in a circuit lead- number of hydrogen particles under just one reason why the construction ing out of the vessel. control. For this reason, a cryogenic of Wendelstein 7-X resembled a gigan- During operation, the baffle plates pump is incorporated into the wall be- tic three-dimensional puzzle, in which of the divertor are exposed to a power- neath the baffle plates of the divertor. components weighing several tonnes ful heat flux of around 10 megawatts In principle, these “cryopumps” work had to be joined together with the per square meter – approximately like a cold beverage can that mists up utmost precision. First, the team in equivalent to the heat output of 4,000 with condensation when you take it out Greifswald worked with partners to typical microwave kitchen appliances. of the refrigerator in summer – except build five 120-tonne modules. Then, “That’s about the most that known ma- that the pump in Greifswald is cooled the fitters used the shed’s overhead terials can withstand,” explains Klinger. using liquid helium at a temperature of cranes to piece these together to form It resembles the conditions experienced -269 degrees centigrade. “As a result, all the torus of the plasma vessel. The by a spacecraft during re-entry into the of the small particles get stuck there,” number of modules depends on the Earth’s atmosphere, which also creates says Klinger. However, the cryopump re- shape of the plasma. “If we could look a hot, glowing plasma. The baffle plates quires the team in Greifswald to accom- down from above, we would see a pen- of the divertor are therefore made of modate additional pipes for liquid heli- tagon with rounded corners,” Matthias the same material as the heat shield um between the water pipes. Hirsch explains during his tour. tiles on the bottom of earlier American Liquid helium is also used to cool It is the complex magnetic field that space shuttles: a carbon composite ma- the large superconducting coils, which makes the stellarator concept more com- terial reinforced with carbon fibers. generate the powerful magnetic field plicated than the competing tokamak The carbon fibers not only provide the composite material with mechani- cal stability but also transport heat toward the vessel wall. Unlike the space shuttle during re-entry, however, these plates need to hold out not just for a few minutes but for almost half an hour. The new divertor – which is currently being installed – must therefore be extremely good at conducting heat between the baffle plates and the water-cooled wall. With this in mind, the Greifswald- based researchers have worked with industry partners to develop a completely new bonding technique. However, heat dissipation is just one of the divertor’s several functions. It is also intended to keep the plasma clean, acting as a vacuum cleaner for impurities arising from unavoidable Anatomy of a plasma: the divertor plates (green) protrude into the convoluted path of the ribbon

Photos: Bernhard Ludewig/IPP (top), IPP (bottom) Graphic: IPP contact between the plasma’s thin out- (yellow). A cross section (right) shows the inner structure of the hot, electrically charged gas.

2 | 19 MaxPlanckResearch 31 principle, which is being used to build the large ITER system in Cadarache, France. With their significantly simpler design, tokamaks have already reached a more advanced stage of development. In 1991, the Joint European Torus (Jet) research reactor in the British village of Culham successfully ran the first short, controlled nuclear fusion experiment in a plasma made of deuterium and tritium. For the first time, the fusion experiment at ITER is expected to deliver more power than is needed to heat the plasma. This net gain in energy would represent a preliminary stage in the development of the first demonstration power plant.

THE TWO CONCEPTS OF NUCLEAR FUSION COMPARED

Compared to stellarators, tokamaks have a much more symmetrical, ring- like plasma shape that – besides its technical simplicity – helps to reduce the impact of potential energy-loss mechanisms. However, this must also carry a powerful toroidal current that holds the plasma together within its tubular magnetic field. This toroidal current leads to additional plasma turbulence, which must be kept under control. In addition, a tokamak works like a large transform- er, with the plasma representing one of the coils. As the plasma current only arises in response to changes in the coil’s current, a voltage is applied to the coil in pulses. Accordingly, a tokamak can only produce pulsed plasma discharges, and so the system is exposed to constantly changing loads. “We want to avoid the constant cyclical loads on the material and the cyclical forces during startup and shut- down,” explains Sibylle Günter, Direc- tor at the Max Planck Institute for Plasma Physics. For this reason, international research is underway into con-

Physicists are sometimes also site supervisors: Thomas Klinger is responsible for plasma research in Greifswald and supervised the construction of Wendelstein 7-X.

32 MaxPlanckResearch 2 | 19 FOCUS_Energy

cepts that can extend these pulses to fusion, says Sibylle Günter. However, several hours or even bring about con- she also raises another key question stant – that is, steady-state – operation. that ITER is meant to resolve: how will In 2016, for example, a team from the the plasma be affected by the result- IPP in Garching used the site’s Asdex ing fusion product – that is, by ex- Upgrade tokamak to demonstrate that tremely fast-moving helium nuclei? it is possible to do this by driving the “For example, these fast helium nuclei plasma flow from the outside. “In the could also trigger instability in the second operating period, ITER is in- plasma,” she says. “It’s a completely tended to test scenarios such as this new area of physics to explore, and I with a view to achieving steady-state personally find that very exciting.” At tokamak operation,” says Günter. any rate, researchers and engineers A stellarator, on the other hand, op- still have a lot of work to do before fu- erates as a purely magnetic cage with- sion energy can be exploited commer- out the ring current, and is suitable for cially. It remains to be seen whether continuous operation from the outset. the stellarator or the tokamak will That’s what makes stellarators such an emerge victorious from this marathon interesting idea. However, in the first effort, but – even at this early stage – few decades of research into these de- the scientists in Greifswald have made vices, the complex shape of their mag- considerable progress with the stellar-

netic field represented an insurmount- ator concept. The first hydrogen plasma: ignited by German able obstacle: for a long time, the Chancellor Angela Merkel on 3 February 2016, systems simply couldn’t confine enough www.mpg.de/podcasts/energie it burned for a quarter of a second and reached hot plasma particles. That changed in (in German) a temperature of 80 million degrees. the 1980s, when theoretical scientists

from the Max Planck Institute for Plas- ma Physics in Garching developed the concept of the advanced stellarator, SUMMARY

whose modular coils featured complex l Nuclear fusion could offer a completely new way of generating energy in the form shapes. Advanced stellarators can now of heat or electricity. Researchers at the Max Planck Institute for Plasma Physics reach the temperatures needed to initi- are attempting to recreate the intense heat of the sun on Earth using the Wendel- ate a nuclear fusion reaction. Part of the stein 7-X stellarator. reason for this breakthrough was that l Inside the stellarator, hot plasma at a temperature of over 100 million degrees must be permanently confined in a magnetic field cage – the experiment is aiming increased computing power made it for half an hour. At the current stage of completion, Wendelstein 7-X has succeeded possible to calculate the complicated in generating hot plasmas at temperatures of over 40 million degrees for half a magnetic field geometry accurately for minute at a time. the first time. l Unlike the competing tokamak principle, which is easier to implement and has Wendelstein 7-X has already pro- already reached a more advanced stage of development, the stellarator allows duced so much new data in the initial continuous operation right from the outset. Its technical exploitation would runs that the physicists have plenty of therefore be more straightforward. analysis to be getting on with during the modification work. If the experi- GLOSSARY ment with the new water-cooling system succeeds in achieving half-hour Plasma: A gas whose atoms or molecules are wholly or partially ionized – in other words, they have had some or all of their electrons removed. A plasma is formed at plasma discharges, that raises the ques- very high temperatures. tion of when we might see the first fu- Stellarator: In a nuclear fusion facility of this type, a twisted plasma would be confined sion power plant based on the stellara- solely by an external magnetic field with a complex shape. Constructing the coils to tor principle. “Give Wendelstein until generate this field is therefore an extremely challenging task. the mid-twenties,” says Klinger. “Sub- Tokamak: In this type of facility, the plasma forms a perfect ring confined by a magnetic sequent development will also depend field, which is in turn partly generated by a ring current in the plasma itself. Without on the results delivered by ITER.” additional technical measures, which are yet to be fully developed, a tokamak can only One of the main objectives of ITER be operated on a pulsed basis.

Photos: Matthias Otte/IPP; Achim Multhaupt (left) is to achieve a net energy gain from

2 | 19 MaxPlanckResearch 33 Climate protection at the chemical plant: in the future, CO2 could increasingly be diverted from some processes and fed into others. Photo: C. Dietl to fuel the chemicalfueltheto industry gas greenhouse A at RWTH AachenUniversity. and Professor of Technical Chemistry Conversion inMuelheiman derRuhr Planck InstituteforChemical Energy Walter Leitner, DirectorattheMax rial forchemicalproduction,” says as anenergyvectorandarawmate- form ofcoal,oil,andnaturalgas–both sorbed thecarbonweusetodayin that werealivemillionsofyearsagoab input. “Throughphotosynthesis,plants they wouldn’t existwithoutnature’s consider theseproductstobeartificial, medications, andinfuels.Evenifwe plastics, inthedyesforourclothes, and cotton. ture provides,includingwood,starch, component of organic matter thatna- livingorganismandisanintegral every carbon formsthechemicalbackboneof hardly surprising – as an element of life, A TEXT for Chemical Energy Conversion by Walter found. led be Leitner That is researchers of task the can and –if suitable production processes plastics and of catalysts products other blocks footprint. Using sources, it from renewable energy could incorporated into be building the dioxide,Carbon all of substances, could help chemical climate the its reduce industry one thing in particular: carbon. That’s But carbonisalsoomnipresentin PETER HERGERSBERG PETER around, youmaywellsee whenyoulook terwards, way youseetheworld.Af Leitner canchangethe conversation withWalter - - in Muelheim an Ruhr. der terials. Aboveall,Walter Leitnerandhis harm to thereputationoffossil raw ma waste productthatdoesthe greatest sights onCO chemical productionandhas sethis ance onfossilsources ofcarbonin wants to contribute to ending the reli- chemist. Ifnothingelse,therefore,he the chemicalvaluechain,”says sources –and,indeed,oncarbonitself. energy supply’s relianceonfossilre way, wecouldgraduallyeliminateour especially windandsolarpower. Inthis now derivedfromrenewablesources – creasing proportionofourelectricityis many andaroundtheworld,anin duce theircarbonfootprint.InGer are takingactionwiththegoaltore bon cycle.Manynationaleconomies causes animbalanceinthenaturalcar- leased intotheatmosphere,whereit als endupasCO later, allcarbon-containingrawmateri form of economicactivity. Sooner or can no longer rely on this fossil-based theEarthinitscurrentform,we serve However, ifwehumanswanttopre “But we will always need carbon in 2 ofallsubstances–the 2 , mostofwhichisre-

Max Planck Institute at Max the ------where appropriateandtherebypave Planck researcher. chemical industry,” says theMax ly reducethecarbonfootprintof as rawmaterials,wecouldsignificant- tap intothesesources toexploitthem ous industrialprocesses.Ifwecould tities ofCO a non-fossilenergysystem,largequan CO “In principle,wecouldevenrecover INDUSTRY’S CARBONFOOTPRINT CHEMICAL REDUCING THE carbon economy. the wayforadoptionofacircular team wanttouseCO deed, it’s forgoodreasonthatfireex- ly reluctanttogiveuptheoxygen. In- technical terms,thecarbon is extreme- not tosaycompletelyapathetic. In cause CO but it’s tricky to implement. That’s be- lessdependentonfossilfeedstocks, try gant waytomakethechemicalindus- into a raw materialsoundslike an ele- Turning thegreenhouse gasCO 2 fromthe atmosphere. Buteven in 2 is chemically very lazy–if ischemicallyvery 2 areavailablefromnumer- 2 | MaxPlanckResearch 19MaxPlanckResearch FOCUS_Energy 2 toreplaceoil 35 2 -

tinguishers are filled with CO2 in order gas and hydrogen with other chemical to fight flames. building blocks to produce polymers or At the same time, there’s no short- components of drugs directly. “These n times age of substances that bind with oxy- higher-value products are more com- gen even more readily than carbon – petitive than simple building block hydrogen being one example. However, chemicals in the early stages of a circu- Catalysis you first need to break the carbon-oxy- lar carbon economy and are easier to gen bond, which takes a considerable introduce on the market,” says Leitner. amount of energy. “From a climate pro- Caroline Gebauer is another re- tection perspective, that’s why it makes searcher who believes that this form of

sense to use CO2 in chemical produc- CO2 recycling could have a sustainable tion particularly if this energy comes future in the chemical industry. Gebau- from renewable sources,” says Walter er participates in Power-to-X on behalf Leitner. “We’re now developing the sci- of BUND (Friends of the Earth Ger Life-cycle analyses entific and technology basis for these many) and advises the project with renew interfaces between energy and gard to environmental and climate pro- H 2 chemistry – for example, in the Pow- tection. From this perspective, she

CO2 er-to-X initiative.” With Leitner as one currently takes a critical view of syn- of the coordinators, this project is fund- thetic fuels, however, when produced

ed by the Federal Ministry of Education from renewable electricity and CO2. and Research (BMBF) and includes part- “Using electrical energy to produce ners from academia, industry, and oth- hydrogen and then converting that into Above Greenhouse gas as a raw er parts of society. a synthetic fuel consumes several times material: CO2 can react with hydrogen more energy than direct electrical use,” (H2) and other substances to form a TWO AIMS: HIGH-VOLUME AND says Gebauer. “In our view, therefore, variety of products. Catalysis steers these reactions toward the desired HIGH-QUALITY PRODUCTS it’s only feasible in applications such as substance, and life-cycle analyses shipping and aviation, where there is – ensure that the entire process is more One approach to chemical production as yet – no direct electrical alternative.” sustainable than a method based on using CO2 begins with the electrolysis However, Walter Leitner believes there fossil raw materials. of water to produce hydrogen – using is a promising future also for fuels pro- Below CO2 extraction: in principle, sustainable electricity. In future, this duced from wind, solar power, and the it’s possible to filter the gas from ambient air and put it to practical use, could also allow electrical energy to be greenhouse gas CO2. “Such chemical as Climeworks has shown with this stored in times of excess supply from energy vectors allow renewable energies demonstration device. wind turbines and solar panels. Then, to be transported over large distances chemists use catalysts to arrange for a and distributed using existing infra- molecular marriage between hydrogen structure,” says the researcher. “That

and CO2. will form an essential part of a sustain- The researchers in Muelheim envis- able global energy system.” age using this method for synthesis of Whether it’s for a fuel or a plastic,

methanol, formaldehyde, and formic the chemical use of CO2 relies on cata- acid – relatively simple substances that lysts that give the mixture of gases a

are formed when one CO2 molecule re- helping hand – and Walter Leitner’s acts with different numbers of hydro- team specializes in this area. gen molecules in each instance. The Presumably, everyone knows about substances are used on a massive scale the catalytic converter in cars, which in industry as raw materials for a whole converts pollutants into harmless sub- host of products, such as plastics, sol- stances. In very general terms, catalysts vents, agrochemicals, or even pharma- act as the matchmakers in the world of ceuticals. Methanol is also of interest as chemistry: they reduce the amount of a fuel. But Walter Leitner and his team energy needed for a chemical reaction, want to go also a step further than that. steer it in the right direction, and are

They want to combine the greenhouse often instrumental in making a trans- Graphic: designergold based on a draft from the MPG; photo: Project Management Jülich/Carola Sonnet

36 MaxPlanckResearch 2 | 19 FOCUS_Energy

Catalysis research for sustainable chemistry: Christophe Werlé (left) and Alexis Bordet are searching for molecular matchmakers that selectively bring CO2 together with other substances, such as hydrogen.

formation possible in the first place. also be reversed,” says the chemist. It Christophe Werlé, who leads his own

When it comes to using CO2 as a raw turns out that it could – with a molec- working group in Walter Leitner’s De- material, the catalysts must perform all ular catalyst containing the precious partment, is searching for catalysts that

three of these tasks. metal rhodium as its active center. bring CO2 and hydrogen together in The metal center in this type of cat- this way. Sometimes his work also in- IT ALL BEGAN WITH A CATALYST alyst increases the chemical reactivity volves optimizing an existing catalyst. FOR FORMIC ACID of one or both reaction partners – and Here, his first question is always why a the type of metal determines not only catalyst does what it does. In this way, Walter Leitner and his team have been the size of this increase but also how he hopes to identify starting points for

researching suitable catalysts for some much hydrogen the CO2 takes in and improving these chemical facilitators – time – for example, for the production what additional partners it incorpo- for example, in order to boost the yield of formic acid. This molecule is formed rates. However, what comes out of this of the desired product and reduce the

by combining a CO2 molecule with pre- process is also determined by the so- amount of by-products. But Christophe cisely one hydrogen molecule. Leitner’s called ligands, which are often complex Werlé also wants to use catalysts as interest in this reaction did not come organic molecules containing phos- matchmakers in particularly difficult

about by chance – it was with formic phorus or nitrogen as points of contact partnerships, such as that of CO2 and acid that he began his journey into the with the metal. The ligands form a de- hydrogen in formaldehyde.

world of CO2 chemistry while studying fined envelop around the metal center In practice, this requires a great deal for his doctorate at the University of so that, in many cases, the reaction of creativity and, especially, hard work. Regensburg. At that time, he was using partners can only attach themselves at After all, Christophe Werlé and his formic acid as a source of hydrogen for certain positions relative to one anoth- team have set their sights on the inter-

chemical reactions, producing CO2 as a er. Ideally, this leaves them with only mediate products in which the catalyst, by-product. “I asked myself, purely out one way of reacting – the one the leads as a mediator between the starting ma- Graphic: designergold based on a draft from the MPG; photo: Project Management Jülich/Carola Sonnet Photo: Thomas Hobirk of curiosity, whether this process could to the desired product. terials, forms itself only weak bonds

2 | 19 MaxPlanckResearch 37 FOCUS_Energy

with the partners to be. Based on these abundant metal manganese instead of short-lived constructs, the scientists a precious metal and can be used to

can identify the reaction pathways and convert CO2 into methanol. potential alternative routes. However, the problem with the short lifespan is PRECIOUS METAL CATALYSTS that the contacts have no sooner ARE AS YET MORE EFFICIENT formed than they change again. “To allow us to analyze them, we try to stabi- Although Walter Leitner is pleased with lize potential intermediate structures this achievement, he is confident that by varying the ligands,” says Christo- catalysts containing a precious metal phe Werlé. can also be used in chemical produc- Chemical plant in the lab: using a Experiments like these give the tion. After all, he says, the ligands in high-pressure reactor, the researchers chemists in Muelheim hints as to how catalysts for CO2 conversion are often in Muelheim study reactions involving CO2 can be turned into the desired at least as expensive as the metal – and gases such as CO2 or hydrogen (left). products. Recently, a team made up of precious metal catalysts are still in In this miniature version of an industrial plant, Andreas Vorholt is Leitner’s colleagues in Aachen and many cases much more efficient than preparing an experiment to test the Muelheim identified a catalyst that, for the alternatives containing cheaper long-term stability of a catalyst (right). the first time, contains the cheap and metals such as manganese, iron, or Photos: Thomas Hobirk (2)

38 MaxPlanckResearch 2 | 19 All mixed up: if the starting materials and catalyst are dissolved in two immiscible liquids, the chemists in Muelheim use a nozzle loop reactor to achieve the closest possible contact between them. Here, part of the reaction medium is drawn off at the base of the reactor and injected back in under high pressure at the top of the vessel. One of the liquids is therefore dispersed in the other as a multitude of small droplets.

nickel. “Even if that only means you common ground between these two ar- solved molecular catalysts that have can use five percent less of the raw ma- eas so that we can enjoy the best of proven effective in the research lab. The terials in an industrial process, the re- both worlds,” Leitner explains. chemist, who leads a research group of sulting cost advantage often outweighs Alexis Bordet and his team work at his own at the Institute in Muelheim, that of using a cheaper metal in the cat- the boundary between those two worlds. also studied business administration alyst,” says Walter Leitner. What’s Instead of individual metal atoms in and has previously worked as an advi- more, another property of catalysts soluble catalysts, the chemists use me- sor to industry. But it wasn’t the first ought to compensate for the downside tallic nanoparticles and ionic liquids. time that he realized: “There’s a big gap of using rare and expensive metals: the- These substances consist of two charged between what academic research makes oretically speaking, they are not used components, one of which is an organ- possible and what industry goes on to up in the reaction. ic molecule in the form of a short implement. That’s why we want to pro- thread. The scientists in Muelheim vide practical data, so that industry NANOPARTICLES IN A chemically attach these molecular says: that’s really good – why don’t we MOLECULAR CARPET threads to a material such as silicon di- try it too?” oxide, producing a charged molecular In practice, however, catalysts do wear carpet that attracts the metallic nanopar- THOROUGH MIXING FOLLOWED out over time. This can happen because ticles like velour attracts dust. The reac- BY PERFECT SEPARATION unwanted substances attach to them, tion partners then flow across the forming persistent impurities, or be- chemical pile, which is interspersed With this in mind, Andreas Vorholt is cause the ligands, which are often frag- with metal atoms, and are paired off focusing on reactions in mixtures of ile, become damaged. Molecular cata- while traveling through the reactor. liquids that separate from one another, lysts such as those being investigated Here, the team wants the molecular like oil and vinegar in a salad dressing. by the researchers in Muelheim also carpet fibers to do more than just hold In these situations, the catalyst may dissolve in the reaction medium – in the nanoparticles in place. “The ionic find itself in an organic liquid, for ex- what chemists call homogeneous catal- liquids interact strongly with the ample, while the product collects in an ysis – and must therefore be laborious- nanoparticles and can act as a catalyst aqueous solution – or vice versa. But ly separated out once their job is done. themselves,” explains Alexis Bordet. this concept presents chemists with a For this reason, the chemical indus- “We exploit this behavior to combine dilemma: during the reaction, all of the try typically prefers heterogeneous ca- different functions of the two compo- components are supposed to mix thor-

talysis, in which liquid or gaseous start- nents into tailor-made catalysts, which oughly – and, in the case of CO2 and ing materials react on the surface of then allow us to transfer the hydrogen hydrogen, the process even involves solid catalysts – eliminating the need to substances from biomass with a high gaseous starting materials. At the same

for a separation process. However, these degree of selectivity or to CO2 directly.” time, the catalyst and the product are solid matchmakers are harder to sys- While Alexis Bordet is working on supposed to go their strictly separate tematically optimize for a chosen reac- catalyst recycling using his “catalytic ways once the reaction is complete. tion. “We’re therefore working with sci- carpet”, Andreas Vorholt is conducting “It’s like in real life: you always want entists from all Departments of our research into engineering solutions exactly what you don’t have,” says Vor- Photos: Thomas Hobirk (2) Graphic: designergold based on a draft by the MPG Institute to identify the fundamental with a view to helping industry use dis- holt. Indeed, it’s hard to come by a for-

2 | 19 MaxPlanckResearch 39 FOCUS_Energy

and to influence the process, the chemists are setting up lab-scale copies of industrial systems and incorporating a whole host of analytical instruments. “We’re integrating a working section for online monitoring – because how cool would it be if I knew that the catalyst isn’t doing what it’s supposed to do right now, and I could then counter- act that,” says Vorholt.

CO2 AS RAW MATERIAL FOR MATTRESSES AND SPORTS FLOORS

One current example serves as proof that catalysts and chemical processes can actually be adapted to allow the in-

dustrial conversion of CO2. At the CAT Catalytic Center, a joint research center of the company Convestro and Leit- ner’s group at RWTH Aachen Universi- ty researchers have helped develop a

process that can incorporate CO2 into Above Distilled ideas: Sheetal mula in which the reaction partners are a polyol – a key component of foams Sisodiya, Walter Leitner, Christophe fully dissolved in the catalyst solution and adhesives. Werlé, and Christina Erken (from left) discuss new experiments that but the product then fully migrates The company aquires the necessary can put CO2 to use. into the other liquid. CO2 from other chemical processes, Below More climate-friendly in the One way out of this awkward situa- where it arises as a by-product, and uses future: the greenhouse gas can be tion is for the starting materials and the it to replace a proportion of the start- used as a raw material for foams. catalyst to be present separately in the ing material for polyol production – two liquids and for one liquid to then which used to be obtained exclusively be dispersed throughout the other in from petrochemistry. Covestro is now

the form of extremely small droplets. producing the first polyols with a CO2 This provides the future partners with content of up to 20 percent on the a large contact surface where they can scale of a several thousand tonnes. The meet the catalyst and react. Andreas process therefore preserves resources

Vorholt’s team implements this con- and reduces CO2 emissions according- cept using a nozzle loop reactor, in ly, as demonstrated in comprehensive which part of the cocktail is drawn off life-cycle analyses conducted by André at the base of the reaction vessel and in- Bardow, a professor at RWTH Aachen jected back in under pressure through University. Foam whose molecular

a nozzle at the top. “This produces fine framework incorporates CO2 is already droplets, and the reaction proceeds being used to make mattresses and re- much faster than in conventional reac- cently even sports facilities were tors – even though the catalyst is left equipped with flooring based on these

totally separate from the product at the materials that contain CO2.

end of the process,” explains Vorholt. For Walter Leitner, the CO2 mat- In order to gain a better understand- tresses are a perfect showcase – and are

ing of what goes on in their reactors, therefore just the beginning of some- Photos: Thomas Hobirk (top), shutterstock (bottom)

40 MaxPlanckResearch 2 | 19 Photos: Thomas Hobirk (top), shutterstock (bottom) price –onethattakesaccountofthecli afarhigher emissions shouldcarry ceive a bit of helpto get started: “CO based chemicalproductionshouldre processed bythechemicalindustry. available atthesamesitebeforebeing CO sustainably ifitistopartnerupwith newable sources to produce hydrogen electricity mustbeavailablefromre- in largequantities.Moreover, sufficient ly CO ple ishowefficientlyandeconomical- with hiscatalysisresearch. Oneexam- factors overwhichhehasnoinfluence products will, however, also dependon house gasasarawmaterialforother ultimatelyusesthisgreen- ical industry thing much bigger. Whether the chem-

In CarolineGebauer’s view, CO 2 –andthegasesmustbemade Power-to-X: chosen a in reaction the direction. steer to order in – center catalytic active the – atom metal Ligand: instead. catalyst solid a across flow starting materials gaseous or liquid catalysis, heterogeneous In liquid. one in dissolved catalysts all are molecular the and product, the materials, starting the homoge In catalysis, reaction. neous the in up used not is catalyst The place. first the in transformation a possible making in instrumental often is and direction, chosen a in it steers Catalyst: GLOSSARY l l l SUMMARY sources to produce hydrogen, which is then combined with CO with combined then is which hydrogen, produce to sources renewable from energy of use the investigates Power-to-X things, other transition. Among energy the to relating schemes supports (BMBF) Research and Education

2 canbecapturedwhenit’s formed and the products are held in different liquids. different in held are products the and catalyst the which in areactor or liquids, ionic with material abase to attach production processes. production and catalysts molecular suitable for searching are researchers Planck Max af products the from catalysts dissolved separate laboriously to need To the avoid ho green the combine that matchmakers chemical identified already have They CO using to aview With ter a reaction is complete, chemists use metallic nanoparticles, which they they which nanoparticles, metallic use chemists complete, is areaction ter use gas with hydrogen to produce methanol and formic acid. formic and methanol produce to hydrogen with gas use The building blocks of a molecular catalyst arrange themselves around the the around themselves arrange catalyst molecular a of blocks building The A substance that reduces the energy needed for a chemical reaction, reaction, chemical a for needed energy the reduces that substance A One of the Kopernikus projects, with which the Federal Ministry of 2 as a raw material in the chemical industry, industry, chemical the in material araw as 2 - 2 - -

economic catalyst.” catalyst, thiswouldthenprovidethe footprint. “In additiontothechemical sessment tookaccountofthecarbon more competitiveiftheeconomicas bewould the sustainableprocesses sive,” saysthechemist.Butofcourse, processes are costly and energy-inten- spective, particularly where the existing an environmentalandeconomicper with hydrogencanbebeneficialfrom to use.“Eventoday, convertingCO there aregoodopportunitiestoputCO gardless ofthis,Walter Leitnerbelieves carbon taxwouldcertainlyhelp.”Re the Power-to-XexpertfromBUND.“A mate damageassociatedwithit,”says

(in German) www.mpg.de/podcasts/ener 2 .

gie -

2 - - - 2

 network: make theGDCh fulluseof From chemiststo chemists– & life sciences for chemistry     Gesellschaft DeutscherChemiker the Job market –onlineandin Job fairs andlectures Workshops Publications career paths about program for young chemists CheMento – The mentoring www.gdch.de/karriere Nachrichten ausderChemie

SPECTRUM

3D movies from cell membrane

A new microscopy technique is making it possible to watch membrane proteins at work

A research group from Erlangen is shedding new light on cell functioning and thus opening up new possibilities for developing therapeutic drugs. Vahid Sandoghdar and his team from the Max Planck Institute for the Science of Light and the Max-Planck-Zentrum für Physik und Medizin have developed a method known as iSCAT (short for interferometric scattering) to such an advanced level that they can now use it to film proteins in a cell membrane in 3D and nanometer resolution. To do so, the team marks the molecules with individual gold nanoparticles. The gold scatters irradiated light, thus enabling the scientists to pinpoint the proteins. Since cell membranes are involved in numerous cellular processes, studying their movements and behavior can reveal a lot about the way in which cells function. This knowledge is important in medical Road movie with membrane protein: a protein molecule marked terms, as the proteins in cell membranes are susceptible to a with a gold particle (orange circle) can be tracked on its path considerable number of active ingredients. across the cell surface (light yellow line) since the nanoparticle (www.mpg.de/0220191/en) scatters light in a characteristic pattern.

Molecule from the early universe

Astronomers find helium hydride in a planetary nebula

Immediately after the Big Bang 13.8 bil- elements to take place. During this pro- space. Using the far infrared spectrom- lion years ago, the universe was un- cess, ionized hydrogen and neutral he- eter GREAT on board the flying obser- imaginably dense and hot. It was only lium atoms combined to form the heli- vatory SOFIA, an international team led after a certain time that falling tempera- um hydride ion (HeH+) – the first mol- by Rolf Güsten from the Max Planck In- tures allowed the first chemical reac- ecule ever. For a long time, researchers stitute for Radio Astronomy has now tions between the newly formed light tried in vain to find this substance in succeeded in detecting this molecule in the planetary nebula NGC 7027. Plane- tary nebulae are gas envelopes ejected by sun-like stars during the final phase of their lives. At their center sits a spent white dwarf star with a surface temperature of more than 100,000 degrees; this emits energy-rich radiation that drives ionization fronts into the ejected envelope. Model calculations predicted that + HeH+ J=1–› 0 this was where the HeH molecule forms, and the astronomers did indeed strike gold. (www.mpg.de/13392365)

Early molecule: the spectrum of the helium hydride ion HeH+ seen on board the flying observatory Sofia in the planetary nebula NGC 7027. The underlying image was obtained using the Hubble telescope; the sharp transi- 149.1 149.15 tion zone between the hot gas (white-yellow) Wavelength (µm) and the cooler envelope (red) is clearly visible. + This is where HeH is formed. Graphics: Richard W. Taylor/MPI for the Science of Light (top); composition: NIESYTO design; image NGC 7027: William B. Latter (SIRTF Science Center/Caltech) and NASA/ESA; Spectrum: Rolf Güsten/MPIfR, Nature, April 18, 2019 (bottom)

42 MaxPlanckResearch 2 | 19 SPECTRUM

Diet influenced the development of languages On the trail Changed dietary habits encouraged the of the Denisovans development of new sounds

The phonemic inventory of human speech is incredibly di- In 2010, when scientists from the Max Planck Institute for verse, ranging from common sounds such as “m” and “a” Evolutionary Anthropology in Leipzig analyzed a tiny finger to rare click consonants. This range of sounds is generally bone from the Denisova cave in Russia, they hit upon a sci- thought to have become established with the emergence of entific sensation: the genetic material it contained was dis- Homo sapiens around 300,000 years ago. An international tinct from that of Neanderthals and modern humans. The team of researchers including scientists from the Max bone must therefore have come from a previously unknown Planck Institute for the Science of Human History and the hominin. Known as Denisovans, these early hominins must Max Planck Institute for Psycholinguistics is now shedding have mixed with modern humans, as traces of their DNA are new light on the evolution of verbal language. The study still found in Asian, Australian and Melanesian genomes shows that labiodental consonants such as “f” and “w”, even today. Analyses of the genomes of people living in In- which now occur in numerous languages, have only be- donesia and New Guinea have shown that they inherited come widespread over the last 2,000 years – as the result of DNA from not one but two different Denisovan lineages. a change in dental bite. In earlier times, adult humans had The two lineages are so divergent that these two groups edge-to-edge bites in which the incisors met exactly, thus may have been completely separate. Denisovans may even enabling them to chew tough food. As softer food become have lived in the region until around 30,000 years ago. This more widespread towards the end of the Stone Age, this for- means that they may have been one of the last surviving mation was superseded by a dental bite in which the upper groups of hominins. incisors were positioned slightly in front of the lower ones. The Denisovans must therefore have once been wide- (www.mpg.de/13189521) spread; however, fossils of these mysterious archaic humans are still rare. After the bone from the cave in Russia from which the Denisovans got their name, researchers at the Max Planck Institute in Leipzig have now matched another fossil to a Denisovan hominin: a mandible from a cave in Ti- bet. This primitive man lived at least 160,000 years ago. The Lower pension, shorter life place where the mandible was found is located more than 3,000 meters above sea level, thus proving that the Deniso- Income and social status are having an increasing vans had adapted to life in this low-oxygen atmosphere long before Homo sapiens arrived in the region. Earlier genetic impact on life expectancy studies have shown that the Denisovans passed on a gene to the people now living in the Himalayas that enables them On average, men who receive small pensions die five years to survive at these high altitudes. earlier than male pensioners who are better off. This was (www.mpg.de/13386452, www.mpg.de/13329072) the conclusion drawn by scientists at the Max Planck Insti- tute for Demographic Research from their analysis of data provided by the German Pension Fund. Between 1997 and 2016, life expectancy increased in all income brackets. How- ever, at 1.8 years, the life expectancy of the poorest 20 percent in West Germany increased by only half the time gained by the highest income group. In the East, the lowest income group gained three years, while the highest gained 4.7 years. In addition, some of the older population of the former GDR were able to collect hardly any pension entitlement points after the reunification of Germany because they became unemployed or had to resort to margin- al employment. This caused pensions in the East to shrink 2 cm significantly after 1997. Lead author Georg Wenau warns against interpreting pension size as a causal factor affecting life expectancy. Small pensions are frequently the result of Fragment of a Denisovan’s lower mandible found in the Baishiya poorly paid jobs and periods of unemployment. Income Karst cave in Tibet. Compared to Homo sapiens, these prehistoric also correlates strongly with health habits and level of ed- hominins had powerful jaws with unusually large molars.

Graphics: Richard W. Taylor/MPI for the Science of Light (top); composition: NIESYTO design; image NGC 7027: William B. Latter (SIRTF Science Center/Caltech) and NASA/ESA; Spectrum: Rolf Güsten/MPIfR, Nature, April 18, 2019 (bottom) Photo: Dongju Zhang, Lanzhou University ucation. (www.mpg.de/13326414)

2 | 19 MaxPlanckResearch 43 Genetic defectswithoutconsequences SPECTRUM 44 Are fishawareofthemselves? (bottom). properly developing from vessels the prevents gene defective a in mRNA Absent embryos. fish zebra two-day-old of (green) system vascular The de ers aimtocomparepatientswithsymptomsofvarying tients havemildersymptoms.Inthenextphase,research For severaldiseases,thiscouldbethereasonwhysomepa ers, thesethenformmoremRNAtocompensatefortheloss. lated genestotakeoverthetask.Accordingresearch covered thatthemRNAofamutantgenesendssignalsforre Max PlanckInstituteforHeartandLungResearch havedis help ofgeneticallymodifiedzebrafish,scientistsfromthe nucleus tothelocationwhereproteinisformed.With the port theinformationfrommutantgeneoutofcell is playedby messenger RNA molecules(mRNA),which trans them tocompensateforthedefect.Itappearsthatakeyrole to patient,asrelatedgenesbecomemoreactiveinsomeof from patient rious diseases. The severity of a disease can vary Defective DNAsequencesareresponsibleforanumberofse- this mirrortestwasseenasanindica of their ownbodies.Until now, passing pies perceive their reflectionsasimages Chimpanzees, dolphins,crowsandmag The animals appear to recognize themselves in a mirror a in themselves recognize to animalsappear The defect the for compensate genes other that ensure can genes defective of RNA messenger The MaxPlanckResearch MaxPlanckResearch 2 | 19 - - Konstanz havenowdiscoveredthat Planck InstituteforAnimalBehaviorin self-awareness. ScientistsattheMax tion thatthespeciesinquestionpossess

------ing thegenome. tremely difficulttopredicttheconsequencesofmanipulat new treatments.Thestudyalsomakesitclearthatisex grees ofseverity. Thismayenablethemtoidentifygenesfor (www.mpg.de has been painted on their bodies. their on painted been has spot a when mirror the in recognize They fish. other of skin the on parasites on feed ( wrasse cleaner scrutiny: Self-critical (www.mpg.de istence ofself-awarenessinanimals. as thestandardtestforverifyingex whether itshouldcontinuetobeused amine the mirror test and consider results asanincentivetocriticallyex- they aremore inclined to interpretthe wrasse possessself-awareness.Instead, constitute evidencethatthecleaner it is not yet clear whether the results However, accordingtotheresearchers, teria requiredtopassthemirrortest. behavior ofthesefishmeetsallthecri or spotsonothersoftheirspecies.The fish shownointerestininvisiblespots see theminthemirror. However, the painted ontotheirbodieswhenthey tions. Thefishattempttoremovespots cleaner wrassealsoreacttotheirreflec ) live in the sea and sea the in live dimidiatus) Labroides /13336233) /12704402)

- - - - -

Graphics: MPI for Heart and Lung Research (top); photo: A. Jordan (bottom) Graphics: MPI for Heart and Lung Research (top); photo: A. Jordan (bottom)

Photo: shutterstock (top); graphics: NASA/JPL (Neptune), NASA/NOAA/GSFC/Suomi NPP/VIIRS/Norman Kuring (Earth), MPS/René Heller (bottom) Life-saving turnaroundinenergypolicy 18 Earth-sizedexoplanetsdiscovered pler mission. planets fromtheentirebody ofdatacollectedduringtheKe- may beabletoidentifymore than100relativelysmallexo themselves. The astronomers conjecture that their method using asignificantlymore sensitivemethoddevelopedby lyzed some of the data from the NASA space telescope have conditionsthatcouldsupportlife.Theresearchers ana- the smallest discovered to date, while anothermay turn out to searches overlookedthem.Oneofthenewexoplanetsisamong have onethingincommon:theyaresosmallthatprevious discovered 18Earth-sizedexoplanets.Allthesestrange worlds havenow sity ofGoettingenandtheSonnebergObservatory Institute forSolarSystemResearch, theGeorgAugustUniver- found elsewhereintheuniverse.ScientistsatMax Planck ing, astheygivereasontohopethata“secondEarth”may be small ones. Yet these small worlds are also the most fascinat- space, as largeplanets are significantly easier to pinpoint than ever, thispercentage isunlikelytoreflectactualconditionsin these exoplanetsaresignificantlylargerthanourEarth,How- biting starsoutsideoursolarsystem.Around96percent of At present,astronomersareawareofagood4000planetsor- A new method is being used to detect small celestial bodies that previous searches had overlooked had searches previous that bodies celestial small detect to used being is method new A Harmful substances released when burning fossil fuels currently cost millions of human lives every year every lives human millions of cost currently fuels fossil burning when released substances Harmful around 65percent ofthepremature mineral gasandcoalareresponsiblefor the global combustion of mineral oil, ingly beenfoundthatemissionsfrom tistical lifeexpectancy. Ithasaccord substances andhowtheyshortensta result of contamination with noxious be drawnastowhichdiseasesarethe chemistry. Theseallowconclusionsto a modeloftheglobe’s atmospheric study utilizes epidemiological data and sources affectshumanhealth.Their gating howairpollutionfromvarious istry. Thescientistshavebeeninvesti- at theMaxPlanckInstituteforChem- searchers ledbyJosLelieveld,Director reached byaninternationalteamofre- year.ery Thiswastheconclusion ture deathscausedbyairpollutionev- vent more than three million prema- benefit the climate, it would also pre- wouldnotonly eled energyindustry A rapidwithdrawalfromthefossil-fu- ( www.mpg.de /13505027) - - cardiovascular and respiratory diseases. cardiovascular andrespiratory as they significantly increase the risk of dust particles are particularly harmful, deaths causedbyairpollution.Fine pollution. air by posed hazard health the reduce significantly would sources energy fossil from shift a coal: of instead power Wind Kepler -

smaller; EPIC smaller; significantly are green) and orange in (here planets discovered newly 18 The Neptune. planet gas the of size the typically are and Earth the than larger are date to known exoplanets the of all almost planets: of Gallery 201238110.02 EPIC could be hosting liquid water. liquid hosting be could 201238110.02 (www.mpg.de/ able energysources. significantly fromswitchingtorenew- Human health could therefore benefit Neptune Earth 13275159) 2 | MaxPlanckResearch MaxPlanckResearch 19 SPECTRUM 45 Insulin protectsagainstcolorectalcancer cancer. tine, whichinturnencourages thedevelopmentofcolon the intestinalwallandtrigger inflammationintheintes- testinal wall.Thismakesiteasier forbacteriatopenetrate structing theseconnections followinginjuriestothein- with insulinresistancehave greaterdifficultyinrecon the cellsandthuskeepintestineimpermeable.Patients ble fortheformationofzipper-likeconnectionsbetween in theintestinalmucosaactivategenesthatareresponsi - these twodiseasesarelinked:insulinreceptorsonthecells tute forMetabolismResearch havenowfoundouthow er riskofcoloncancer. ScientistsattheMax PlanckInsti- velop so-called"insulinresistance".Theyarealsoatgreat - people commonlyde- hormone. Thisiswhyoverweight Excess weight can stop insulin receptors reacting to the Signaling pathway in the intestinal mucosa strengthens the intestinal barrier intestinal the strengthens mucosa intestinal the in Signaling pathway SPECTRUM 46 tile environmentforhumans:diseases, Tropical rainforestsareactuallyahos- animal speciesmakethejungleless limited resources and the indigenous Early settlers in Sri Lanka specialized in hunting small mammals small hunting in specialized Lanka Sri in settlers Early Monkey huntingensuredsurvivalintherainforest MaxPlanckResearch MaxPlanckResearch ( www.mpg.de/ 12791681) 2 | 19 ture andprovidesmallerquantitiesof ample, aremuchmoredifficulttocap- arboreal monkeysandsquirrels,forex- than attractiveforcolonization.Agile - functioning insulin signaling pathways (right). pathways signaling insulin functioning mal with mice in absent are These (left). cells intestinal the between formed are red) (bright connections mice, healthy In protein thanlargeanimalsthatlivein this difficult-to-catchresource isanoth not exploitedexcessively. “Theuseof sure thatthenatural environment was full-grown animalswerekilledtoen- hunting strategywassustainable–only ile mammalssuchasmonkeys.Their tually specializedinhuntingsmall,ag- They havefoundthatearlysettlersac- piens adaptedtothisenvironment. gained new insight into how Homo sa- has for theScienceofHumanHistory team ledbytheMaxPlanckInstitute est 45,000yearsago.Aninternational were alreadylivinginthelocalrainfor- Sri Lanka prove that modern humans open savannas.However, findsmadein ers. Human History, oneofthestudylead- Max PlanckInstitutefortheScienceof explains Michael Petraglia from the nological flexibility of Homo sapiens,” er exampleofthebehavioralandtech- Lankan jungle. Lankan Sri the in cave Fa-Hien the in found been humans by used tools bone and stone rainforest: the in home At ( www.mpg.de /12746043) years ago have ago years 45,000 - -

Photo: O. Wedage (top); graphics: MPI for Metabolism Research/ Ostermann (bottom) Photo: O. Wedage (top); graphics: MPI for Metabolism Research/ Ostermann (bottom)

Graphics: MPE (top); photo: Anna Preis (bottom) Chimneys intheMilkyWay ships areunstable. pear tosufferparticularlywhentheirsocialrelation- within the group. As with humans, chimpanzees ap- tainty that arises when they are competing for status iological. Themalesarestressedbythesocialuncer- stress appearstobepsychologicalratherthanphys- havior among themselves during these times. The in stableperiods–despiteshowinglessaggressivebe- This meansthattheanimalsweremorestressedthan times ofsocialinstabilityandincreasedcompetition. the male chimpanzees’ hormone levels are higher in stress hormones in their urine. The results show that Coastandmeasured the national parkontheIvory thebehaviorofmalechimpanzeesinTaïserved AnthropologyinLeipzigob- tute forEvolutionary national research teamfromtheMaxPlanckInsti many advantagesbutalsocomesatacost.Aninter- For speciesthatliveingroups,higherstatushas Center Galactic the of map x-ray new a on structures unusual discover Researchers Social uncertaintyalsoputschimpanzeesunderstress Male animals are less aggressive if social relations in their group are unstable are group their in relations social if aggressive less animals are Male maintain and conflict of escalation the prevent to order in instability social of times in aggressively less behave chimpanzees Male Fermi bubble Fermi southern the of Base plane Galactic bubble Fermi northern the of Base

the coherence within the group. the within coherence ( www.mpg.de/ light years light 150 13295691) clearly visible north and south of the galactic plane. galactic the of south and north visible clearly are – chimneys discovered recently the – structures Elongated Way. Milky the of region central the from emissions x-ray the shows image false-color this galaxy: our of heart the into look A able distancefromthecenter. Astron lactic planebutbeginssomeconsider of which stretches far beyond the ga with theso-calledFermibubbles,each entists havelongsincebeenfamiliar around 50lightyears.Moreover, sci only extendtodistancesofup show outflowsfromthecenterthat Galactic center. Thesewingsorlobes detected bipolarbulgesclosetothe ertheless, astronomershavelongsince permassive black hole, are rare. Nev- energy fromitscenter, thesiteofasu tranquil galaxy. Giganticoutburstsof Our MilkyWay isacomparatively

------bles. and transportthemtotheFermibub out ofthevicinityblackhole neys apparentlyblowenergyandmass base oftheFermibubbles.Thechim gions oftheGalacticCenterto from thewingsininnermostre- further out.Theseappeartoextend galactic planewithstructuresmuch our Milky Way north and south of the connect innerregionsofthecenter images: two widegaschimneys that discovered anewstructureinx-ray for ExtraterrestrialPhysicshavenow omers ledbytheMaxPlanckInstitute (www.mpg.de/ 2 | MaxPlanckResearch MaxPlanckResearch 19 13261062 ) SPECTRUM 47 - - SPECTRUM

Fruit bats are reforesting African woodlands

800 hectares of new forest could grow every year from the seeds scattered by the fruit bats

Intact ecosystems are not only a joy for nature lovers, they are also useful in financial terms. However, it is usually difficult to calculate how much money they actually bring in. Scientists from the Max Planck Institute for Ornithology in Radolfszell and colleagues from Sweden and Ghana have now calculated the ecological and financial benefits of straw-colored fruit bats in Africa for the first time. Every night, these bats fly long distances to their feeding grounds while scattering the seeds of the fruit they consume. According to the researchers, a colony of 150,000 bats can scatter more than 300,000 seeds in a single night. This means that 800 hectares of woodland could be reforested every year in Ghana alone – by just one colony. However, the number of straw-colored fruit bats in Africa is on the decline. The animals are at risk from hunting and the logging of large trees. Both forests and humans would benefit from better protection. (www.mpg.de/13271542) Straw-colored fruit bats love fruit more than anything.

The roots of A leap towards superconductivity apple trees at room temperature

The history of the apple is closely linked with that of humankind. However, it Fewer power plants, fewer greenhouse sius and at pressures of less than 1.7 seems likely that humans were not the gases and lower costs: if scientists were megabar, i.e. 1.7 million times atmo- first to make apples a big thing. As Rob- to discover superconductivity at room spheric pressure. Until now, the record ert Spengler from the Max Planck Insti- temperature, this could drastically cut for high-temperature superconductiv- tute for the Science of Human History electricity consumption. This is be- ity was minus 70 degrees Celsius; since in Jean reveals in a new study, there is cause superconductors transport elec- 2015, this has been held by hydrogen fossil and genetic evidence to indicate tricity without loss. A team at the Max sulfide, which also has to be subjected that apple trees developed large, fleshy, Planck Institute for Chemistry has to extremely high pressure. sweet fruits millions of years before moved one step closer to this goal. The (www.mpg.de/13512517) they were domesticated. These were researchers led by Mikhail Eremets an attractive food source for large have been synthesizing lanthanum The pressure is on: more than one million bar can be generated between two conically cut dia- mammals, which were classified as hydride. This hydrogen-rich bond with monds in an anvil cell not even the size of a fist. megafauna and also distributed the ap- the metal lanthanum loses its electri- This makes lanthanum hydride superconductive ples. However, most species of mega- cal resistance at minus 23 degrees Cel- at relatively high temperatures. fauna became extinct at the end of the last Ice Age. As a result, populations of wild apple trees became isolated until humans began transporting the fruit, particularly along the Silk Road. Thus the lineages once again came into contact and produced hybrid varieties that bore even larger fruit. Humans then reinforced this characteristic by refining and planting seedlings from the most popular trees, thus laying the founda- tions for the wide variety of apples available today. (www.shh.mpg.de/1321592) Photos: MPI for Ornithology/ Ziegler (top); Thomas Hartmann (bottom)

48 MaxPlanckResearch 2 | 19 Photos: MPI for Ornithology/ Ziegler (top); Thomas Hartmann (bottom) Overview_Black Holes

A picture of a dark monster. The image is the first direct visual evidence of a black hole. This particularly massive specimen is at the center of the supergiant galaxy Messier 87 and was acquired by the Event Horizon Telescope (EHT), an array of eight ground-based radio telescopes distributed around the globe.

A portrait of a black hole

Black holes swallow all light, making them invisible. That’s what you’d think anyway, but astronomers thankfully know that this isn’t quite the case. They are, in fact, surrounded by a glowing disc of gas, which makes them visible against this bright background, like a black cat on a white sofa. And that’s how the Event Horizon Telescope has now succeeded in taking the first picture of a black hole. Researchers from the Max Planck Institute for Radio Astronomy in Bonn and the Institute for Radio Astronomy in the Millimeter Range (IRAM) in Grenoble, France, were

among those making the observations. Photo: EHT Collaboration TEXT HELMUT HORNUNG

n spring 2017, scientists linked up objects at extremely small angles of less tion of the Max Planck Institute for Ra- eight telescopes spread out over than 20 microarcseconds. With that dio Astronomy. In the 2017 observing one face of the globe for the first resolution, our eyes would see individ- session alone, the telescopes recorded time, forming a virtual telescope ual molecules on our own hands. approximately four petabytes of data. with an effective aperture close to This is such a huge volume that it was the Idiameter of the entire planet. The THE DATA ARE PROCESSED IN A actually faster and more effective to technique is called Very Long Baseline SUPERCOMPUTER send the data by post than via the In- Interferometry (VLBI), which combines ternet. The data were calibrated and the signals of the individual antennas The Event Horizon Telescope (EHT), as analyzed at the Massachusetts Insti- into one image. This synchronization the network of observatories is known, tute of Technology (MIT) in the U.S. requires highly-precise atomic clocks, included the 30-meter IRAM dish in and at the Max Planck Institute for Ra- accurate to a billionth of a second. The Spain and the APEX telescope in Chile, dio Astronomy using supercomputers technique makes it possible to resolve which is operated with the participa- known as correlators. >

2 | 19 MaxPlanckResearch 51 Overview_Black Holes

Event horizon Ring singularity Left Beyond the horizon. The graphic depicts a rotating black hole. The ergosphere is the area in which no particles can remain at rest. The event horizon can be regarded as the surface of the black hole; anything that moves beyond it, quite literally vanishes from the world. Right Space antenna. The 30 -meter IRAM dish is the most sensitive single telescope in the Event Horizon Telescope’s worldwide array.

Ergosphere Inner horizon

“The results have given us the first clear ed in the campaign with the 30-meter The heart of the supergiant galaxy M87 glimpse of a supermassive black hole. telescope. At 2800 meters above sea lev- has two particular characteristics that They mark an important milestone in el on Mount Pico Veleta in the Spanish make it a good candidate for the pro our understanding of the fundamental Sierra Nevada, it is the most sensitive ject. It is both unusually massive and processes underlying the formation single telescope in the EHT array. “We relatively close to Earth, which makes and evolution of galaxies in the uni- can adjust the antenna’s surface with a it easier to see. This makes it a perfect verse,” says Anton Zensus, Director at precision on the scale of a human hair,” target for astronomers who, with the the Max Planck Institute in Bonn and says astronomer Pablo Torne. global telescope array, finally have an Chairman of the EHT Collaboration instrument capable of directly targeting Board. Zensus considers it remarkable IDEAL WEATHER CONDITIONS such an exotic object. that the project’s astronomical observa- AND FUNCTIONING TECHNOLOGY The regions around supermassive tions and theoretical interpretation black holes are subject to the most ex- were achieved faster than expected. Over four days in April 2017, Torne and treme conditions known in space. Black According to IRAM Director Karl his colleagues at IRAM simultaneously holes are fascinating cosmic objects Schuster, the success is based on “de- aligned their telescopes on the center that incorporate an incredible total cades of European expertise” in milli- of the galaxy M87 and its gigantic black mass within a tiny volume of space. meter astronomy: “Back in the 1990s, hole for the first time, along with the Their mass and thus their gravitational the Max Planck Institute for Radio As- other EHT stations located around the pull are so great that even light can’t es- tronomy and our Institute with its two globe. “We couldn’t have wished for cape them. That’s what makes them observatories was demonstrating tech- better weather conditions for the time black, making it impossible to directly nically and scientifically that our of year. Most importantly, the observa- observe them. high-resolution radio observations rep- tory’s equipment worked perfectly, The only way to actually observe resented a unique method for analyz- from its high-precision atomic clock such cosmic gravity traps is to image ing the immediate vicinity of super- and receiver systems to its data record- their “shadow”. This is caused by the massive black holes.” ers,” says Torne. In total, the observa- extreme bending of light – shortly be- IRAM, a facility co-financed by the tions recorded at the 30-meter antenna fore it irretrievably vanishes into the

Max Planck Society, actively participat- alone exceeded 500 terabytes of data. black hole. By making extremely pre- Graphic: designergold based on a draft from the MPI for Gravitational Physics

52 MaxPlanckResearch 2 | 19 Photo: IRAM/DiVertiCimes a journeyofaround55million light bent andamplifiedlikebya lens.After around themassivemonster isbeing light from the strongly heated matter ring-like structureintheimage: the and compactobject.Thisexplains the massive at highspeedsaroundthisvery black hole.Ahotgasplasmaismoving dark centralregion–theshadowof shows a ring-shaped structure with a quency of230gigahertz)andclearly 1.3 millimeters (correspondingtoafre leased, wasobtainedatawavelengthof to theedgesofblackholes. dense dustandgascloudsrightthrough range, astronomerscanseethroughthe inthemillimeter cise observations The image, which has now been re- » it is smaller and lies within the dark area. dark within the lies and smalleris it image; the visibleinnot is itself horizon event The - shoots outa“jet”ofmatter atleast Virgo active. Its nucleus Aandisvery known asastrongradiosource called under number87.Thegalaxy isalso Charles Messiercataloged the object ter. In1781,the Frenchastronomer near thecenterofVirgo galaxyclus pergiant ellipticalgalaxyknownasM87, dark area. age; itissmallerandlieswithinthe horizon itselfisnotvisibleintheim- than lightthatmovingaway. Theevent coming towardusappearsbrighter fect. Astheblackholeisrotating,light in theringareduetoarelativisticef- ray. Thevariationsinbrightnesswith- years, itarrivesattheEHTtelescopear- The originoftheblackholeisasu- - observations. tent withthatderivedfrom previous lion Suns.Thefigureishighly consis- been calculatedasequivalent to6.5bil mass of the black hole in M87. This has accurately determinethe enormous andallowsthemto central machinery deal aboutthenatureofgalaxy’s The shadowtellstheresearchers agreat MACHINERY OFAGALAXY A GLIMPSEINTO THE CENTRAL perpendicular tothedisk. high velocityasatightlyfocusedbeam black holeatitscenterandemitted celerated in the accretion disk of the 5000 light years long. This has been ac-

2 | MaxPlanckResearch 19MaxPlanckResearch 53 > -

A giant in the sky. The supergiant galaxy Messier 87 was one of the targets of the Event Horizon Telescope observation campaign. The jet visible in this optical image of the galactic nucleus clearly originates from the supermassive black hole in the center of the elliptical galaxy.

Anton Zensus considers the success to be a watershed moment in astronomy. “In the future, researchers both in and well beyond our field will clearly de- lineate periods before and after this discovery,” says the Max Planck researcher. He believes astronomers will learn more about galactic nuclei and obtain a complete picture of how active galaxies are formed and evolve. In addition, he anticipates the discovery will allow us to test Einstein’s general theory of relativity ever more rigorous- “For many decades, the only way to tivity range and gain even more fasci- ly. “Black holes, after all, are an ideal detect black holes was indirectly,” says nating insights,” says IRAM Director laboratory to test what happens in Michael Kramer, Director at the Max Karl Schuster. strong gravity.” Planck Institute for Radio Astronomy. Then, a few years ago, scientists suc-

ceeded in detecting gravitational waves for the first time, allowing us to “hear” the effect of merging black SUMMARY holes on space-time. l Astronomers have taken the first picture of a black hole. It resides at the center “Now we can finally see them as well, of the supergiant elliptical galaxy M87, about 55 million light years away. giving us the fascinating chance to l The discovery was made by combining observations made in April 2017 from an study in a unique way these exotic array of radio antennas distributed around the Earth to form a virtual telescope. objects and the extreme curvature l This was done using very-long-baseline interferometry (VLBI), a technique that they impose on space-time,” says combines the signals of the individual antennas. Michael Kramer, a leading scientist in l Researchers hope that images of black holes will help them better understand the BlackHoleCam project, which is galactic nuclei and provide insights into the formation and evolution of active galaxies. part of the Event Horizon Telescope consortium totaling roughly 200 researchers. GLOSSARY THE OBSERVATION REPRESENTS Accretion disc: A disk of matter rotating and coalescing towards (accreting) a central ob - A WATERSHED MOMENT ject, for instance a black hole. It can be composed of atomic gas, plasma (ionized gas) or interstellar dust. Toward the center, the speed of rotation and temperature rise sharply. The observations are ongoing. At the Arc second: The term arc second is often employed as an expression of a telescope’s re- end of 2018, NOEMA in the French solving power, the smallest angle it can successfully resolve. An arc second corresponds th Alps joined the global array. This sec- to one 3600 of a degree. A microarcsecond is one millionth of an arcsecond. ond IRAM observatory has twelve Charles Messier: French astronomer (1730–1817) whose career began in the French Navy, before leading him to France’s Bureau of Longitude. He discovered 20 comets and created highly sensitive antennas, making it a catalog of 103 diffuse astronomical objects, which have since been discovered to be gas the most powerful in the EHT in the nebulae, star clusters, and galaxies. northern hemisphere. “NOEMA will

allow us to venture into a new sensi- Photo: NASA, ESA and the Hubble Heritage Team (STScI/AURA)

54 MaxPlanckResearch 2 | 19 Interview_Black Holes

“An astounding coincidence with theory”

Max Planck Director Anton Zensus on the first observation of the shadow of a black hole

What sounds paradoxical is reality: Black antennas via software. This “phasing” was The key word is very long baseline interfer- holes have a shadow! In the Messier 87 an enormous technical challenge for us and ometry (VLBI). We aim several radio tele- galaxy, astronomers were able to observe was essential for the EHT. The weather con- scopes, which are far away from each oth- such a phenomenon for the first time with ditions also played into our hands – they er, at the same celestial object at the same the Event Horizon Telescope (EHT). The Max were really good right from the start. time. The signals collected are combined in Planck Institute for Radio Astronomy in a special computer – the correlator. In this Bonn had a first row seat. Anton Zensus What does an observation with eight way, a virtual telescope is created. This pro- heads the “Very-Long-Baseline Interferome- telescopes look like? vides an image sharpness corresponding to try” Department. The Department deals with a technique that enabled discovery in the first place. We talked to Anton Zensus, This marks the culmination of a long period Chairman of the EHT Collaboration Board, » about how the successful observation came of development. about and what the results mean.

Mr Zensus, how long has the Event Horizon Telescope project been running? Anton Zensus: Officially, it started two years ago. But the preparations have been going on for a decade. And if you factor in the preparatory and pioneering work, it’s actually 20 years. During this time, we have fundamentally improved the quality of our measurements and have already investigated important questions about active galaxies like M87 – such as the nature of the gigantic matter jets from their central regions. In this sense, we have now reached the peak of a long development.

You say that EHT had only been conducting observations for two years. Were you surprised by your success after this relatively short time? Yes indeed! It was also astonishing that so many things worked right away. After all, the Event Horizon Telescope consists of a combination of eight different telescopes. One of these telescopes – which is called ALMA – is located at an altitude of 5000 m in the Chilean Atacama Desert and comprises 66 individual antennas. In order to be able to integrate this system into the Anton Zensus, Director at the Max Planck Institute for Radio Astronomy and Chairman of the EHT Collaboration Council. Photo: Helge Horn Photography EHT, we had to interconnect all individual

2 | 19 MaxPlanckResearch 55 that of a single antenna with the diameter glish astronomer Arthur Eddington mea- therefore appear black to us. According to of the distance between the most distant sured this phenomenon during a total so- theory, outside the event horizon, attract- antennas – in the case of the Event Horizon lar eclipse when he observed a small shift ed by the enormous mass, there is a huge Telescope, this is about 8000 km. Just of the star positions near the solar disk. By amount of gas swirling around in a vor- imagine: if your eyes were as sharp as the the way, that was on 29th of May 1919 – ex- tex-like disk structure at tremendous EHT, you could theoretically read a news- actly one hundred years ago. This com- speeds. The gas heats up and begins to paper in New York from Bonn. However, pletes the circle. glow. Relativistic particles – those that the EHT does not see any optical light but move at almost the speed of light in a mag- rather radio radiation with wavelengths of The black hole in the center of the Milky Way netic field – also release synchrotron radia- just over one millimeter. is much closer than that in Messier 87. Why tion. So around a black hole, it “shines”, was the EHT still successful with M87? while the hole itself, as the name suggests, How is your Institute involved in the Event Our Milky Way is a bit hesitant to disclose appears black. It is this blackness that we’ve Horizon Telescope? its deepest secrets (laughs). But joking been observing. The EHT includes the 12-meter APEX tele- aside, there are, of course, sound reasons. scope, which is operated by our Max On one hand, the heart of our Milky Way is What did you discern from the shadow? Planck Institute for Radio Astronomy to- hidden in a dense fog of charged particles. To be honest, we were amazed at how well gether with the European Southern Obser- This leads to a flickering of the radio radi- the dark spot we observed matches the vatory and the Swedish Onsala Space Ob- ation and thus to blurred images of the structure predicted by our computer sim- servatory. It is located close to the ALMA center of the Milky Way. But I am confident ulations. From the shadow itself, the mass, site. The Max Planck Society is also in- that we can still solve this problem. On the the rotation, and the magnetic field of the volved with the IRAM 30-meter antenna other hand, galaxy M87 is about 2000 black hole can be derived. For this purpose, on the Pico Veleta in the Spanish Sierra Ne- times further away. However, the black 60,000 different simulations of black holes vada and will be involved with the NOEMA hole in its center is also 1000 times more were carried out on the computer and telescope near Grenoble in the future. A to- massive than the one in our Milky Way. The compared with the EHT results. tal of thirteen partner organizations from greater mass makes up for the greater dis- all over the world work for EHT. Our Insti- tance. The shadow of the black hole in M87 How will this successful observation tute operates a supercomputer that cali- therefore appears to us to be about half advance astronomy? brates and evaluates the data. In fact, the size of the one from the gravity trap in Black holes are an ideal laboratory for mea- enormous amounts of data are generated. our Milky Way. surements under strong gravity. We are at Each of the EHT’s individual telescopes de- the beginning of a phase in which many liver around 350 terabytes per day. Just what is the shadow of a black hole? new insights await us. We will soon be able A black hole deflects the light even more to confidently exclude alternative explana- You knew what you were looking for: the than our sun. The theory of relativity pre- tions for black holes – such as boson stars shadow of a black hole. I suppose theoretical dicts that a radiation ring should be ob- or gravastars. We will better understand considerations played an important role? served around a dark spot where the black the galactic centers and obtain a complete Yes, Einstein’s general theory of relativity hole is located. Right where the black hole picture of the formation and evolution of of 1915 provides the theoretical back - is. Some casually refer to this dark spot as active galaxies. We will also be able to ob- ground. Also about a hundred years ago, the shadow of the black hole. serve pulsars in the vicinity of the black astronomers observed jets for the first hole in our Milky Way and thus thoroughly time. These are gas flows that shoot out of But where does the light come from? check the general theory of relativity. the center of active galaxies and must be Black holes are black, aren’t they? generated at enormously high energies. According to the general theory of relativi- The interview was conducted by Helmut Hornung Since the 1970s, we have suspected that ty, black holes have an “event horizon”. It de- there are super-massive black holes behind scribes the region within which nothing it. The theory of relativity predicts that a can escape from the black hole. The event massive object can deflect light. The En- horizon – but also the area within – should

56 MaxPlanckResearch 2 | 19 Optical: DSS; illustration: NASA/CXC/M. Weiss of the darkthebodiesof mystery The T ral philosopher. versity; hewasalsoadedicated natu- Hebrew andGreek at CambridgeUni- chell hadnot only studiedtheology, highly regardedscholar. Indeed,Mi memorial inthechurch, wasalsoa chell, who,asisclearfromhistablet eval church liveditspriest,JohnMi TEXT than more 230 predicted first such were exotic objects Telescope now allowed has shadow time. the us to ablack of see It hole for first the is that startling space space bend around an and them. irresistible They time and exert Event The attraction. Horizon have only they indirectly on due gravitational to the couldn’tthat observed, they directly be effect Even have though they alarge mass, black are not holes made matter. of Until recently, that meant the 18 HELMUT HORNUNG HELMUT th century nearthetown’s century medi- shire. For26yearsduring English countyofYork- town ofThornhillinthe gins inthequiet little of black heholes be- story - - ment that a very massive star’sment that a very gravity it, hereasonedinathought experi ture onthegravityofstarsin 1783.In august institutionthathegave alec- of theRoyalSocietyinLondon. John Michellbeingelectedamember scientific community, anditresultedin causedquiteastirinthe This theory of differenttypesbelowtheground. earthquakes werepropagatedbywaves earthquake in 1755,hesuggested that an essaypublishedaftertheLisbon His waschieflyinterestedingeology. In It was before the members of this

years ago. years - Simon deLaplacesuggestedinhis1796 cian, physicist,andastronomer Pierre- up thesubject.TheFrenchmathemati - chell, anothernaturalphilosopher took us,” heconcluded. bodies ...theirlightcouldnotarriveat should reallyexistinnatureany[such] be abletoleaveitssurface.“Ifthere might besostrongthatnolightwould emits X-rays in the process. the in X-rays emits and star massive blue neighboring a from material up swallows X- Cynus the swirl: Cosmic More thanadecadeafterJohn Mi- 2 | MaxPlanckResearch 19MaxPlanckResearch _Black Holes History 1 blackhole 57

58 Schwarzschild radiusofsuch anob the basisofgeneralrelativity. The trically-charged, staticblack holeon and behaviorofanon-rotating, elec- Schwarzschild hadcalculated thesize in 1916,however, theastronomer Karl matics article inthejournalA our world. radiation wouldsimplydisappearfrom point singularitiesinwhichmatterand did, indeed,predicttheexistenceof on hisequationspublishedin1915,he ence –albeitnotintentionally. Based ofthese“darkbodies”intosci- entry relativity, who paved the way for the of stein, withhisgeneraltheory scurity. Intheend,itwasAlbertEin ly overlookedandquicklyfellintoob- and Pierre-SimondeLaplacewerelarge on thephysicalworldofJohnMichell obscur, a“darkbody.” Laplace termedsuchanobjectacorps ed ofcorpuscles,itssmallest particles. ofIsaacNewton,consist cepted theory this light,accordingtothegenerallyac light wouldnotbeabletoescapethem; that theircouldbemassivestarswhose work sibility ofsuchblackholes.Previously MaxPlanckResearch 2 MaxPlanckResearch But in1939Einsteinpublishedan However, thethoughtexperiments Exposition duSystèmeMonde attemptingtodisprovethepos- | 19 nnals

M athe ------deed, aftertheinitialhype, interest in initially disregardedbyscience. In toimmune skindisease. tions. He diedon 11 May1916 ofanau exact solutionsofEinstein’s fieldequa- ern FrontinRussia–heformulatedthe lieutenantontheEast- was anartillery middle of World War I – Schwarzschild in1909.Afewyearslater,ry inthe - rector oftheAstrophysicalObservato gen toPotsdam,wherehebecameDi- him via Munich,Vienna, and Goettin- astronomical careerwentontotake stars.His orbits ofplanetsandbinary in arenownedjournalcalculatingthe the age of 16 he published two papers talent wasevidentatanearlyage.At a German-Jewishfamily, Schwarzschild’s Frankfurt astheoldestofsixchildren rapid scientificsuccess.Bornin1873 In hisshortlife,Schwarzschildenjoyed EINSTEIN’S FIELDEQUATIONS EXACT SOLUTIONSOF size ofacherry. proximately onecentimeter, orthe For theEarth,thisradiuswouldbeap- beyond which nothing can return.ary pendent onitsmassandisthebound- ject, named after the astronomer, is de But the subject of black holes was - - - escape them. escape to able be not would light whose stars massive be could their that suggested Laplace de Pierre-Simon astronomer and physicist, mathematician, French the portant means of describing objects short wavelengthX-rayspectrum.Uhu- theskyinextremely cally tosurvey al astronomy. Itwaslaunchedspecifi - ru Right relativity. general of basis the on hole black static electrically-charged, non-rotating, a of behavior and size the calculated Schwarzschild Karl astronomer Left mately 30timesthemassof the Sun.It with abluesupergiantstar approxi that theX-raysource wasassociated Cygnus X-1.Astronomersdiscovered tion ofCygnusstoodout.Itwas named one particularobjectinthe constella mostly neutron stars. Among these, ru who diedin2018. English physicistStephenHawking, studied thembecamestars–likethe taking centerstage.Scientistswho ory. Andthisledtoblack holesalso using newconceptsderivedfromthe- pected propertiescouldbedescribed present inextremestates.Theirunex- or neutronstarsinwhichmatteris theoreticians, forexample,whitedwarfs that, initially, of werethesolepreserve eral relativity”occurred. Clifford Will, “therenaissance ofgen- After this,inthewordsofphysicist tween themid-1920sandmid-1950s. steadily. Thiswasintheperiodbe Einstein’s system of thought waned - usheredinaneweraofobservation discoveredhundredsofsources, In theearly1970s,satelliteUhu- General relativitybecameanim Advanced mathematics. In In mathematics. Advanced Thought experiments. In 1796 1916 , , the the

- - - -

Photos: akg-images (2) History_Black Holes

Astronomers concluded that approximately 4.5 million solar masses must be » concentrated in a region the size of our planetary system.

has an orbital companion of approxi- concentrated in a region of space the they were able to take a picture of its mately 15 solar masses, and this must size of our planetary system. A massive- “shadow,” an observation which is con- be a black hole. ly compact mass of that kind can only sidered the first direct evidence of a The X-ray emission can be explained mean one thing: a gigantic black hole. gravity well on a galactic scale. by matter falling in toward the black Our Milky Way is also not an excep- But black holes had already been hole due to its gravity. This forms an action. Scientists believe that such mas- making headlines just a few years ear- cretion disk around the companion due sive monsters lurk in the centers of lier. In September 2015, scientists con- to its extreme gravity, swirling around most galaxies – some even more pow- firmed Einstein’s prediction of gravita- it at unimaginably high speed and erful than Sagittarius A*. The supergi- tional waves, with the source calculated heating up to several million degrees ant galaxy Messier 87 has a black hole as the merging of two black holes of 36 due to friction. of about 6.5 billion solar masses! Like and 29 solar masses. The 230-year-old Cygnus X-1 is by no means the Sagittarius A*, this star system, at a dis- history of black holes is far from over. only black hole that astronomers have tance of approximately 55 million light Instead, these observations mark the indirectly detected. They now know of years, was one of the targets of the beginning of a new era in astronomy, many, with a mass ranging from four Event Horizon Telescope. The team, in- which will shed light on the dark uni- to sixteen solar masses. One, however, deed, have succeeded in their goal. It verse – and on the dark monsters that is a great deal more massive. It was dis- was announced on 10 April 2019 that lurk in it. covered at the end of the 1990s and resides at the heart of the Milky Way, some 26,000 light years away. In 2002, a group led by Reinhard Genzel from the Max Planck Institute for Extrater- restrial Physics made another sensa- tional discovery. At the Very Large Telescope of the European Southern Observatory (ESO), the scientists made observations of a star that was approach- ing the center of our galaxy to a distance of only 17 light hours (around 18 billion kilometers). In the following months and years, they kept track of the orbital motion of this S2 star, as it was termed. It orbits the galaxy’s central region, Sagittarius A*, at an average speed of 5,000 kilometers per second and with a period of 15.2 years. The motion of S2 and other stars led astronomers to conclude that some 4.5 million solar masses must be

Ripples in space-time. In 2015, astronomers detected gravitational waves for the first time – the image is based on a “numerical relativity simulation.” It depicts two black holes merging deep in space. Photo: S. Ossokine, A. Buonanno (Max Planck Institute for Gravitational Physics), Simulating eXtreme Spacetimes project, W. Ben ger (Airborne Hydro Mapping GmbH)

2 | 19 MaxPlanckResearch 59 BIOLOGY & MEDICINE_Plant Research

Fill up the bowl!

Leghold traps, limed rods, pit traps - insectivorous plants have come up with unusual strategies to obtain additional nutrients. Axel Mithöfer at the Max Planck Institute for Chemical Ecology in Jena is investigating how pitcher plants from Southeast Asia entrap and digest their victims.

TEXT CATARINA PIETSCHMANN

lants that consume animals – there are also purely practical ways of us- That’s why, if you have a carnivorous imagine coming up with an ing them. In Malaysia, for example, the plant at home, you shouldn’t fertilize idea like that! Evolution, traps of the pitcher plant, Nepenthes, are it. “If they can meet their needs for nu- though, doesn’t suffer from filled with sticky rice, vegetables, or trients using their roots, they form qualms. Pitcher plants are ex- meat and eaten. On the island of Bor- fewer traps and instead invest more traordinaryP and have long been a source neo, old pitchers that have lignified are energy in leaves for photosynthesis,” of curiosity and flights of fantasy. used as storage vessels for food and explains Mithöfer. Charles Darwin went as far as to drink or for steaming rice. Of all the insectivorous plants, the dedicate an entire book to these plants, Venus flytrap, Dionaea muscipula, with commonly referred to as carnivorous. FLUID WITH MEDICINAL POWERS its traps reminiscent of leghold traps, is Of the sundew’s trapping mechanism, the most spectacular. It is native to he wrote: “It is surprising how minute The plants are even said to be good for North American bogs and is the best a particle of any substance, ... if placed your health. Indigenous peoples, for ex- known active trapper. The waterwheel in actual contact with the surface of a ample, treat skin inflammations and di- plant, Aldrovanda, indigenous in Ger- gland, suffices to cause the tentacle to gestive disorders with the digestive liq- many but now extinct there, does pos- bend. [...] It is a much more remarkable uid from the pitchers. sess a very similar trapping mechanism fact that when an object, such as a bit Axel Mithöfer also has a practical to the Venus flytrap. Its leaves, howev- of meat or an insect, is placed on the use for insectivorous plants. “In sum- er, are only a few millimeters in size, disc of a leaf, as soon as the surround- mer, I place two or three sundew plants and the plant grows under water, making tentacles become considerably in- next to the fruit bowl. That deals with ing it relatively unknown. With its ten- flected, their glands pour forth an in- any problems with fruit flies.” tacles that twist around its prey, the creased amount of secretion.” The additional nutrition the plants sundew is also an active trapper. It’s not just our fascination with get from animals helps them to keep The Venus flytrap snaps shut on

plant carnivores that have attracted us; up in nutrient-poor environments. its victims at a surprising speed for a Photo: Anna Schroll

60 MaxPlanckResearch 2 | 19 Under UV light, the trap of a pitcher plant resembles a filigree work of art. Insects are attracted by nectar on the rim of the pitcher and slip into the belly of the trap. The lid prevents rain from diluting the digestive fluid in the trap. Photo: Anna Schroll BIOLOGY & MEDICINE_Plant Research

Chitin receptors signal the presence of prey to the pitcher plants » – in the true sense of the word, they taste their food.

plant. Mithöfer gives me a demonstra- and digestive juices are secreted from of the Venus flytrap, and Mithöfer’s tion of the trapping mechanism in the glands in the trap, bathe the prey and team already possess that of one pitch- greenhouse of the Max Planck Institute dissolve it. The same glands then ab- er plant species of the genus Nepenthes. in Jena. He carefully strokes a fine twig sorb what the hungry plant lacks in its over an open trap, touching the tactile nutrient-poor habitat: nitrogen and NEW TASKS FOR PROTEINS trigger hairs inside it a few times. The phosphate compounds. plant has three of these hairs, barely The feast lasts several days. Then From their genes, it’s clear that carniv- visible to the naked eye, on each half the trap unfolds again and spits out the orous plants have important things in of the trap leaf. “bones” – the indigestible chitin exo- common, even if they developed the skeleton of the fly. In the wild, the next ability differently. They all use the en- STRUGGLING IS DEADLY rain shower washes out the remains of zymes that evolution passed them down the banquet. from their ancestors. “Plants have been The trap snaps shut in a tenth of a sec- The sundew does things entirely dif- exposed to herbivores and pathogens, ond. “If the fly were smart, it would ferently. If an insect lands on its leaves, such as fungi, for 400 million years. stay motionless for two hours. The trap which are covered with fine tentacles, And that’s the reason why they devel- would then open, and it could fly off,” it gets trapped by countless droplets of oped enzymes like chitinases that can explains Mithöfer. But staying standing a sticky liquid. After this, the tentacles break down the cell walls of fungi,” said still isn’t in the nature of flies. Under- at the edge of the leaf first maneuver Axel Mithöfer. standing why isn’t hard. Caught be- the animal into the middle of the leaf, It’s a fortunate coincidence that tween the trap leaves, it panics and where many of the glands that produce the carapace of insects is also made of struggles wildly to free itself. digestive juice are located. The leaf then chitin. Carnivorous plants take advan- Each time it touches a trigger hair, slowly curls over the “meal”, and the tage of this fact and simply re-deploy it generates a tiny electrical impulse, prey is digested. their existing tools, turning defensive just like that in a nerve cell. “The plant There have been multiple indepen- enzymes into digestive secretions. sums the impulses to determine if it dent instances of plants developing They can now use chitinases to has actually caught living prey, or if ways to consume animals. Depending break down the chitin shells of insects only a drop of rain has landed on it,” on the expert you ask, there have been and get at the nutrients within. The Mithöfer explains. “Two, three con- four to nine separate lines of develop- plants get the nitrogen and phosphate tacts are okay. But nine or ten means ment. The genomes of some species from the bodies of the insects using it’s curtains for the fly!” A plant that such as of a bladderwort, Utricularia proteins and enzymes that digest nu- can actually count! gibba, and the Australian Albany pitch- cleic acids. While the trap leaves squeeze to- er plant, Cephalotus, have already been Mithöfer’s particular field of exper- gether tightly and crush the insect, the deciphered. In Wuerzburg, researchers tise is pitcher plants. There are just over

flytrap literally starts to salivate. Acid are currently working on the genome 120 species of the genus Nepenthes in Photos: Anna Schroll (3)

62 MaxPlanckResearch 2 | 19 Above left The Venus flytrap has a sophisticated capture mechanism. The leaves have been repurposed as folding traps and contain trigger hairs, which send signals to the plant when an insect is trapped. Within fractions of a second, the two leaf halves snap shut and capture the prey. Above right The various species of sundew – here the Cape sundew – in contrast rely on sticky traps. Looking like sweet nectar on red flowers glittering in the sunlight, the traps are actually covered with a sticky liquid designed to attract and hold insects. Below Alberto Dávila-Lara is a doctoral student in Axel Mithöfer’s research group. The photograph shows him collecting nectar from the rim of a pitcher. Photos: Anna Schroll (3)

2 | 19 MaxPlanckResearch 63 the humid tropical rain forests of At its rim, the pitcher secretes nectar, “We do that to prevent flies from escap- Southeast Asia, most of them, climbing which becomes exceptionally slippery at ing or something else from falling into plants. Four species of Nepenthes grow high humidity. There’s no way of grip- the pitcher.” in the greenhouse of Mithöfer’s Insti- ping, even using the fine adhesive pads And how do the pitchers sense that tute in Jena. of insects feet. Incautious insects fall and prey is near? Unlike the Venus flytrap, Pitcher plants primarily prey on soil drown in the fluid of the pitcher. Nepenthes produces chemical rather insects such as ants and termites. After Axel Mithöfer investigates how di- than electrical signals. The plant’s traps a pitcher has matured and filled to a gestive secretions are generated by feed- probably have receptors for chitin – the good quarter with fluid, the lid opens ing the pitchers with fruit flies and substance that forms the carapace of and the “hunting season” commences. then placing nylon socks over them. insects. While other plants use recep-

Above Using a sterile syringe, Alberto Dávila-Lara extracts digestive fluid from an unopened pitcher for further analysis. Below left A fluorescence microscope reveals the glands in the pitcher wall that produce the digestive fluid. Below right The glands lie in depressions of the epidermis and are covered by protruding hoods (The bar corresponds to one-twentieth of a millimeter). Photos: Anna Schroll (above), MPI for Chemical Ecology (below, 2)

64 MaxPlanckResearch 2 | 19 BIOLOGY & MEDICINE_Plant Research

Simple leaf Nepenthes leaf

Leaf base

Leaf base = Petiole/stalk = Lamina basal lamina-shaped structure tendril

Petiole Lamina = pitcher

Metamorphosis from leaf to trap: over the course of evolution, the leaf base of an ordinary leaf in Nepenthes has developed into a basal structure and the petiole into the tendril of the pitcher. The leaf lamina eventually developed into the actual trap.

tors to detect predators, pitcher plants on the body of the pitchers are not only as long as possible. If too many insects use theirs to sense the presence of prey. sweet, they also glow violet under black are caught, the plant can no longer pre- So, in the true sense of the word, they light in the laboratory. Chemical anal- vent bacteria from proliferating in the taste their food. ysis of the nectar revealed that this is pitcher fluid. When this happens, the probably due to a flavonoid. “Maybe trap is broken down and discarded. CHITIN PROMOTES DIGESTION it’s this glow that attracts the insects,” says Mithöfer. LEAVES CONVERTED INTO TRAPS “As soon as the receptors detect the To prove their hypothesis, Mithöfer chitin of an insect’s carapace, a signal and his team intend to test the behav- Even if the pitchers are usually striking- cascade is triggered that activates the ior of ants by comparing how they be- ly colored and patterned, they’re not production of digestive enzymes,” says have presented with natural Nepenthes the flowers, but elongated, widened, Mithöfer. One of the cascade’s most im- nectar and then with an artificial nec- and specialized leaves – a beautiful ex- portant signaling substances is the phy- tar lacking the flavonoid. To perform ample of how plant leaves can perform tohormone jasmonic acid, which is also the experiment, they plan to fly an en- a variety of tasks. They hang from the used to defend against predators. The di- tire ant colony, including the queen, plants in all stages of development: un- gestive enzymes originate from glands from Indonesia to Jena. ripe and closed, active with the lid open, in the lower third of the pitcher. These The pitcher fluid does already con- and shriveled and dead. If a pitcher is glands have two functions. “They both tain small amounts of enzymes before incapable of consuming food, it is usu- exude secretions and also transport the the first prey lands in it. But it can take ally only discarded when the plant has nutrients from the prey into the plant.” between two and three days for enough extracted as many nutrients as possible Typically, it’s in their flowers that digestive enzymes to form. “Nepenthes from it. A pitcher plant, after all, doesn’t plants secrete nectar; Nepenthes, on the can take its time; the prey isn’t going have resources to spare. other hand, generates it at the rims of anywhere. It’s a real gourmet!” Not all carnivorous plants catch its pitchers. And the nectar isn’t used to Mithöfer’s team extracted the fluid their own food. Some have a “delivery attract pollinators, but, instead, to from still young, unopened pitchers service” and reward the couriers with catch prey. Unlike flower nectar, which and discovered potassium chloride, sweet rewards. There are also Nepen- can contain aromatic substances, pitch- trace elements, digestive enzymes, and thes species that provide shelter for er nectar is entirely odorless. Even so, naphthoquinones. As soon as the trap ants. They live sheltered in cavities of ants and beetles are tremendously at- has caught something, it produces addi- the pitcher plant and, in return, de- tracted to it. tional digestive enzymes and acid to ac- fend their landlady against predators. Mithöfer’s doctoral student Alberto tivates the enzymes. The naphthoqui- They themselves are unaffected by the Dávila-Lara discovered that the rim of nones have an antimicrobial effect and digestive juices, which they simply

Photos: Anna Schroll (above), MPI for Chemical Ecology (below, 2) Graphic: MPI for Chemical Ecology pitchers and the dot-like nectar glands probably keep the juice free of germs for swim through. >

2 | 19 MaxPlanckResearch 65 BIOLOGY & MEDICINE_Plant Research

“Insight must precede application.” Max Planck

The Max Planck Society is a world-leading insti- tution pursuing basic research in a wide area of sciences and humanities. Research is performed

at Max Planck Institutes ↘ within Germany and at a few other locations world-wide. Directors lead an institute jointly with their fellow directors and pursue a bold research agenda within their Axel Mithöfer is investigating independent departments. the signal cascades used by plants to protect themselves from predators and pathogens. The Max Planck Society is seeking nominations for Insectivorous plants have modified some of the molecules in the cascades to turn themselves into predators. A bushy angelica grows in the tea room of Mithöfer’s MAX PLANCK DIRECTORS research group, but ... it wouldn’t harm a fly.

We are looking for the strongest and most To nominate an outstanding scientist, please The plant also benefits from extracting creative scientists worldwide. Core criteria for provide a letter of support. For self-nominations, the valuable nutrients from the waste directorship are scientific and scholarly excel- please upload a letter of motivation including material of the ants. In some instances, SUMMARY lence, an innovative and visionary research a two to three page research proposal, your this type of nutrition can take on biz- l There have been multiple instances of plant species independently evolving program, and personal and intellectual leader- CV, a publication list and three to five selected zare forms. “On the island of Borneo, as carnivores to consume insects. ship, rather than seniority. Max Planck Directors publications. tree shrews and rats sit on the rim of l Few plants species have evolved the ability to eat insects as new inventions; enjoy complete scientific freedom. We offer an particularly large pitchers of certain instead, they have tended to repurpose existing tools. international and excellent research environ- For online nominations and more information Nepenthes species, lick sweet nectar l Pitcher plants do not attract insects with the smell of the nectar they secrete

ment, outstanding infrastructure, and compe- including a list of Max Planck Institutes, please from the inner surface of the lid – and on the rim of their pitchers. Instead, the nectar reflects ultraviolet light, and ↘ simultaneously release their droppings this is probably what attracts insects. titive long-term scientific funding. Excellent visit the * Nomination Portal URL* . into the pitcher. Another Nepenthes administrative support enables our directors to species provides daytime shelter for focus on research. Nominations should be submitted by 28 Oct. 2019 bats, whose excrement they then uti- GLOSSARY lize,” Mithöfer explains. The Max Planck Society strives for gender equity Nominations will be treated with strictest confi- Besides carnivores and excrement Pitcher plants: At present about 120 Nepenthes species are known, and researchers are and welcomes nominations of candidates with dentiality and later nominations may also be feeders, pitcher plants can even be her- still discovering new species. Their range extends from Madagascar to New Caledonia and from China to Northern Australia. The leaves consist of a leaf base, a tendril, and diverse backgrounds. We actively encourage considered. bivores. Nepenthes ampullaria with its the actual pitcher trap. Some species have traps up to 50 centimeters in size. Many nominations of persons with disabilities. large pitcher openings, for example, Nepenthes species are threatened with extinction due to loss of habitat and illegal trade. waits for leaves to fall into its pitcher. Venus flytrap: The traps of these carnivorous plants capture insects by snapping shut A plant that, during the course of on them, after which they begin by exposing them to hydrochloric acid from gland evolution, consumes first light, then cells. After a delay of a few hours, the glands also release digestive enzymes. The bro- animals, and finally other plants – ken down nutrients are then absorbed by the same glands. These glands, are therefore similar in function to roots. This explains why only those genes that are typical for both Nomination portal: could there be any better way of leaves and roots are active in the trap cells. https://www.mpg.de/career/commoncall demonstrating nature’s almost infinite

versatility? Photo: Anna Schroll

66 MaxPlanckResearch 2 | 19 Photo: Anna Schroll MAX PLANCK DIRECTORS nominations ofpersonswithdisabilities. diverse backgrounds. We actively encourage and welcomesnominationsofcandidateswith The MaxPlanckSocietystrives forgender equity focus onresearch. administrative enablesourdirectors to support titive long-termscientificfunding. Excellent ment, outstandinginfrastructure, andcompe- international andexcellent research environ- enjoyfreedom.scientific complete We offer an ship, rather thanseniority. MaxPlanck Directors program, andpersonalintellectual leader- lence, aninnovative research andvisionary directorship are scientificandscholarlyexcel- creative scientistsworldwide.Core criteriafor We are lookingforthestrongest andmost The MaxPlanck Society isseeking nominationsfor precedeapplication.” “Insight must independent departments. and pursueaboldresearch agendawithintheir lead aninstitutejointlywiththeirfellow directors at afew otherlocationsworld-wide. Directors at sciences andhumanities.Research isperformed tution pursuingbasicresearch inawidearea of The MaxPlanckSocietyisaworld-leadinginsti- * Nomination Portal URL* visit the* NominationPortal including alistofMaxPlanckInstitutes,please Forand moreonline nominations information publications. CV, apublicationlistandthree to five selected a twoto three pageresearch proposal, your please uploadaletterofmotivation including Forprovide self-nominations, aletter ofsupport. To nominateanoutstandingscientist,please considered. dentiality andlaternominationsmay alsobe Nominations willbetreated withstrictestconfi- be submittedbyshould Nominations https://www.mpg.de/career/commoncall Nomination portal: Max Planck Institutes ↘ within Germanyand ↘ 28 Oct. 2019 Max Planck . Programming fairness

In the future, it will be more and more common for computers to make decisions about human beings – whether they are granting loans or assessing applicants. However, it happens occasionally that the automated systems that are already in use discriminate against certain groups of people. Niki Kilbertus and Bernhard Schölkopf, researchers at the Max Planck Institute for Intelligent Systems in Tuebingen, want to change this by developing fair algorithms.

TEXT TIM SCHRÖDER

everal blackboards are dotted Balanced calculation: around the hallways of the algorithms must Max Planck Institute for In not discriminate against particular telligent Systems in Tuebin groups of people, such gen. Scientists walking past as women or men. canS use these to note down their thoughts. They are also places for re searchers who happen to meet in the corridors to discuss new ideas. “It’s real ly helpful,” says Niki Kilbertus, “because I have to develop so many ideas right now.” He is referring to concepts that go far beyond those he has dealt with in the past. Niki Kilbertus has degrees in mathematics and physics. He is familiar with the rigorous formal methods for solving complex matters, and he knows how to program algorithms. For his doc torate, however, he has ventured be yond the boundaries of formal langua ges. He is addressing a question that has been the subject of heated public de bate for a while now: whether and to

what extent algorithms can be fair. Photo: Alamy

68 MaxPlanckResearch 2 | 19 MATERIALS & TECHNOLOGY_Machine Learning

Computers are sober machines that are gence. This is not their only concern, chine learning. This means that they incorruptible and are never wrong – or they also demand that companies must enable the computer to gradually im- so one might think. Nevertheless, de- be held accountable for their algo- prove through learning and experience. bate about computer algorithms dis- rithms, calling for responsibility and It is a challenging task. So far there criminating against people flared up at accountability. Critics also expect trans- is no technical solution that allows for the end of 2018. It had become known parency when it comes to how and why fairness to be instantly realized across all that a large online retailer was planning particular decisions are made based on applications. It is likely that this is not to use a computer for pre-screening ap- calculation specifications. The commu- going to change in the future either: plicants, and that it had emerged even nity is called FAT: fairness, accountabil- “There can be no solution that answers in the trial phase that the computer was ity, transparency. every possible question. Each situation more likely to reject applications re- is different, and needs to be analyzed ceived from women than those from ANY DISCRIMINATION MUST separately,” says Kilbertus. “And the sec- men. This led to an outcry in the me- BE ANALYZED CAREFULLY ond step is at least as elaborate: we need dia, not least because experts envisage to find a mathematical description for that in the future, computers will be Niki Kilbertus is a doctoral student in the real-world problem.” making decisions about human beings the Cambridge-Tuebingen-Program run The algorithmic analysis process al- more and more often, using vast by the Max Planck Society, and works ways follows a clear formula: data is amounts of data that are now available. at the Max Planck Institute in Tuebin- collected and fed into an analysis pro- It would be scandalous if these comput- gen as well as at Pembroke College in gram, whose algorithms will then issue ers favored or discriminated against Cambridge. He and his colleagues are a recommendation such as “applicant particular groups of people. exploring the part of FAT that can be not suitable”. To ensure that this auto- Initiatives have been formed around translated into technology: the re- mated process is always fair in the fu- the world in light of such scenarios, searchers strive to teach fairness to al- ture, it would need to be improved on promoting fairness in artificial intelli- gorithms. To do so, they rely on ma- both the data and the output side. >

2 | 19 MaxPlanckResearch 69 MATERIALS & TECHNOLOGY_Machine Learning

machine learning cycle

status quo (e. g. burglary statistics)

measurements collecting data data

machine learning

model

society

recommendations, predictions, decisions

“First, you need to examine which data ular city district were less likely in the Above Real-life feedback: a machine is collected, and how, and then check past to pay back their loans, the algo learning algorithm solves a question, which decisions are finally issued by rithm could, for example, use the place such as which neighborhoods are likely to experience a lot of burglar- the computer, and the reasons behind of residence as an indicator for future ies. For this purpose it is trained them,” explains Niki Kilbertus. These applicants. The algorithm does not un using data about the status quo, for analyses always touch on data protec derstand in this context that the place example, data regarding the econom- tion issues as well. “This is always about of residence is unlikely to have a direct ic and social situation, and crime rates. The algorithm then develops a sensitive personal data, after all. This causal impact on creditworthiness, and model, based on which it issues means that we also need to find solu that there are likely to be other, more predictions, decisions, or recommen- tions for analyzing data without dis relevant factors at play. dations. If criminal acts are then closing it.” prevented in a particular neighbor- The young researcher is part of hood due to increased police pres- THE ALGORITHM WOULD NEED ence, society and thus the state of the working group led by Bernhard TO VERIFY ITS ASSUMPTIONS the world is changed. The algorithm Schölkopf, Director of the Max Planck then has to adjust the model based Institute for Intelligent Systems in Tue Systems are often trained using histor on new data. bingen. Both researchers deal with the ic data about credit repayment behav Right Freedom for ideas: Mateo basic issue of causality in machine ior. Personal data, such as the place of Rojas-Carulla, Niki Kilbertus, and learning: the question as to what extent residence of a new applicant, are then Nadine Rüegg (left to right) are discussing various aspects of artifi- computers can draw meaningful con used to calculate their creditworthiness: cial intelligence. clusions between different aspects. This how likely is it that the applicant is go very question is also a central aspect ing to pay back their loan? However, when it comes to the issue of fairness. the computer may unintentionally dis Niki Kilbertus has an example: the criminate against individuals, since a granting of loans and checking of cred creditworthy person might live in an itworthiness. Things can get critical if area to which the algorithm attributes simple algorithms are used that are a poor reputation. based purely on correlations “if X, then “The algorithm would basically

Y relationships”. If residents of a partic need to be equipped to verify its as Graphic: MPI for Intelligent Systems

70 MaxPlanckResearch 2 | 19 sumptions on a regular basis,” says Niki among which it can happily establish Simpson’s paradox is another illustra Kilbertus. For example, by using specif correlations that are often likely to tion of the importance of correct iden ic criteria to occasionally grant a loan have nothing to do with the true caus tification of causal connections. It was to an individual that is initially not rat al connections. named after the British statistician Ed ed as creditworthy. Economists refer to ward H. Simpson, who demonstrated in this approach as explore versus exploit. TRUE CAUSAL CONNECTIONS the 1950s that a particular combination To explore is to test new solutions in ARE KEY of data from different groups, such as this context. To exploit, on the other women and men, will give rise to seem hand, is to utilize an existing approach Niki Kilbertus uses a far-fetched exam ingly paradox situations. One classic as effectively as possible, to avoid the ple to illustrate this point. An algo example of a Simpson’s paradox dates effort required for a new development, rithm could detect that people who are back to 1973. There was a sense of out for example. In the case of granting more likely to repay their loans tend to rage at the time, when out of the wom loans, the explore approach would pro be tidier and more likely to stick felt en who had applied for a place at the vide for loans to be occasionally ap gliders under the chairs in their home. University of California in Berkeley in proved contrary to the original rules. If A calculation specification does not per the U.S., a smaller percentage had been the person turns out to pay back the se understand correlations, so it may accepted to take up studies than was loan after all, the algorithm has to be conclude that it is a good idea to give the case for male applicants. adjusted and improved. a pack of felt gliders to new borrowers It turned out, however, that this was This example shows that in some in order to increase their creditworthi not a case of discrimination. An analy cases, the data that is currently used is ness. “We need to understand the caus sis of the data conducted later on not sufficient in order to make fair de al connections to be able to ask any showed that more women had regis cisions. Niki Kilbertus: “When it comes meaningful questions, such as wheth tered for extremely popular subjects in to fairness, the challenge is to discover er the individual would have repaid the the fields of humanities and social sci and understand the true causal struc loan if they had lived elsewhere,” says ences. They were therefore on the ture underlying the data as far as possi Niki Kilbertus. By contrast, incorrect whole rejected more often than men, ble.” This approach is intended to pre causalities such as the link between who more frequently applied for less vent an algorithm from considering possessing felt gliders and repayment sought-after subjects such as chemistry

Photo: P. Junker / MPI for Intelligent Systems data as being merely a table of figures behavior could be eliminated. or engineering. The paradox was that

2 | 19 MaxPlanckResearch 71 MATERIALS & TECHNOLOGY_Machine Learning

Teaching machines: Bernhard Schölkopf teaches algorithms to recognize true causal connections among data. This also promotes fairness of decisions made by computers.

er, the supposed unfairness can be ex plained by the fact that the doctor is lacking experience in working with par ticular groups of patients. Whether an algorithm is going to make fair decisions in the future also depends on how companies or people in general define or perceive fairness. “The ultimate goal is that an algorithm should always make the right deci sion,” says Niki Kilbertus. “But first we for each Department in isolation the cluded to create truly fair calculation have to clarify for each case what right percentage of women accepted for specifications. An algorithm with mul even means.” most courses of study was even higher tiple levels of fairness so to speak. There is something else that needs than that of accepted male applicants. to be taken into account: decisions However, across all disciplines, the EVEN PEOPLE ARE NOT made by computers can have an active proportion of male applicants that ALWAYS FAIR impact on the world. One example of were accepted was slightly higher. “To this are modern programs that use understand the causal connection cor Nevertheless, he also points out that we data about cases of burglary and theft rectly, we first need to have the right should not get carried away too easily. in a city to determine which neighbor data and to know which Department “People make decisions about other hoods are most likely to experience the women applied for. Gender has an people every day. It is often complete further burglaries. The algorithm’s impact on the choice of subject. Only ly unclear why an individual makes a statement will then lead to increased then are we able to correctly interpret certain decision. At the same time, we police presence in these areas, and pos the situation,” says Kilbertus. demand that an algorithm must always sibly to an increase of crimes detected. Bernhard Schölkopf even goes a make decisions that are one hundred It is conceivable, however, that it was step farther when it comes to the issue percent correct and fair.” At the end of not actually the case that more crimi of correct causalities. He also addresses the day, studying fairness in machines nal offenses were committed in these the question “where does fairness be also leads to the insight that human be neighborhoods. Possibly, it was simply gin?” Does it begin with asking wheth ings are also not always fair. Quite sim that more crimes were detected be er African-American applicants have ply, we make mistakes, for example due cause the police patroled these areas the same opportunities in the U.S. as to a lack of information or experience. more frequently. their white competitors? “Or do you Much like machines. A dermatologist “The decisions based on an algo have to go back further, and take into for example, who spent their entire ca rithm can therefore lead to wrong con account the fact that colored children reer screening only light-skinned peo clusions. We refer to this as a feedback do not have the same educational op ple for skin cancer, may be more likely loop, in which the algorithm has an portunities as white children, and that to mis-diagnose dark-skinned people, impact on real life.” Another similar ex this has an impact on their entire ré and to possibly overlook a tumor. This ample are traffic warnings issued by sumé and their future job prospects?” means that dark-skinned people would navigation services. If a road is busy, Schölkopf raises the question of wheth not receive the same quality of treat the service will recommend switching

er aspects like this should also be in ment as light-skinned people. Howev to other routes, and after a short while, Photo: Wolfram Scheible

72 MaxPlanckResearch 2 | 19 Sunrise!

The Foundation funded a 130-meter Helium balloon for the Max Planck Institute for Solar System Research, enabling one of the world’s largest solar telescopes to get off the ground. Sami Solanki‘s SUNRISE telescope observed the sun’s magnetic fields traffic will build up on these routes. tend to mention social commitment in high resolution. As a result, re- This is why Niki Kilbertus points out or related activities in their applica search on how the sun in fluences that it is important to keep not only tions, while men are more likely to sig the earth system can fairness in mind, but also possible feed nal dominance and to come across as now be carried back effects. more competitive,” Kilbertus explains. out more In the context of his doctorate, he “These aspects could be the very char has analyzed a number of cases of dis acteristics that the company is looking effectively. crimination and made initial attempts for.” As Bernhard Schölkopf points to describe the respective problems out: “It is incorrect to assume that we mathematically. “Programming takes at can generally achieve fairness, by least as much time again as analyzing withholding certain details such as each case.” And yet for the time being, gender from the algorithm.” This fair- he and his colleagues are focusing ness by unawareness approach is far mostly on analysis. “Each algorithm from infallible. works based on specific criteria that are Whichever way fairness might be used to derive a statement. We are now taught to algorithms, it is a rather soft trying to find out where the criteria fail; criterion compared to the purely math to find the weak point.” ematic formalisms Niki Kilbertus used An interesting question in this con to deal with in the past. While he does text is why the algorithm by the on appreciate being able to produce clear line retailer mentioned above seems to evidence for or against a statement, he have discriminated against female ap also finds this new aspect very reward plicants. It is unknown how the algo ing. “It is interesting to work on an is The Max Planck Foundation has rithm works in any detail, but Kilber sue of such social relevance,” he says. supported the Max Planck Society tus has a hunch. “It is fair to assume He soon realized that knowledge in the that they set out to analyze the appli fields of mathematics and computer for more than ten years by providing cations in an anonymized form.” So sciences is not enough for his research targeted funding for top-level in - the system would not have known the work. So he decided to learn about so no va tive and cutting-edge research applicants’ names or their gender. cial sciences and legal issues. He hopes at the more than 80 institutes, Nevertheless, the system failed. “Oth that he is now well-equipped for find enabling breakthroughs in frontier er studies have shown that women ing truly fair algorithms. science. As a patron, you can make a crucial difference by creating

ad ditional scope to keep this SUMMARY re search ahead of the curve in the

l Algorithms make decisions about human beings more and more often. Discrimi- inter national scientific competition. nation occurs time and again in this context, not least because incorrect causal Join us! connections are established from data, such as links between an individual’s place of residence and their creditworthiness. Max Planck-Foundation l In their endeavor to teach fairness to algorithms, the researchers at the Max Planck Institute for Intelligent Systems in Tuebingen analyze the data used by Deutsche Bank the calculation specification and how decisions are made in each individual case. IBAN DE46 7007 0010 0195 3306 00 l Based on their findings concerning true causal connections that provide answers to questions such as “Which person is going to pay back a loan?”, the researchers are drafting mathematical descriptions for the respective issues at hand.

www.maxplanckfoundation.org CULTURE & SOCIETY_Personal Portrait

The art of orientation

Every city map, and every map in general, contains stories about the time at which it was produced. At the Bibliotheca Hertziana, Max-Planck-Institut für Kunstgeschichte in Rome, art historian Tanja Michalsky is studying how people have measured the world. Her research is expanding the area covered by her subject and even includes films by Federico Fellini and David Lynch.

TEXT MARTIN TSCHECHNE

rom the roof of the library, a century old. My host’s extended arm the yearning to ascend beyond long- the city unravels like a to- picks out the Pantheon and Trajan’s gone eras, at least for a while.. Did this scale map. Fantastical maps Column from the swirling mix of dif- city actually exist before it was invent- of this kind have been con- ferent epochs – triumphal remnants of ed by Federico Fellini? Or did the great trived by novelists such as Roman antiquity. Far below on the Via director merely create a perfect image UmbertoF Eco, while others, including Gregoriana, the narrow street in front of it with films such as “Roma” or “La Jorges Luis Borges and Michael Ende, of the building, cars and rattling Ves- dolce vita”? have created images that conform en- pas push their way between the people “Go to the Fontana di Trevi,” the art tirely to reality but must be understood walking by. This is Rome, in the spring historian advises me. “Experience the as a paradox and nothing more than an of 2019. The present day. A courtyard crowds. And ask yourself what the idea idea. In this realm, literature enjoys al- opens out on the opposite side, and is that makes so many people want to most unlimited freedom. Here, howev- from the vantage point of the high-up go there.” Day and night, the police are er, the observer is presented with a work research Institute, a roof garden can on hand to prevent visiting couples of art in real life, as though spread out also be seen, with a rusty railing run- from climbing over the edge of the for study purposes: an undulating sea of ning between red bricks, chairs, a rota- baroque fountain into the light blue roofs and gables, towers and churches ry clothes dryer, and a few pots with water kissing as passionately as Anita protruding out from them with the sprawling green plants. Ekberg and Marcello Mastroianni did in cupola of Saint Peter straight ahead – a Fellini’s 1960 classic, with its story of bright spot just in front of the horizon. ROME IS A JUXTAPOSITION the sweet life of Rome’s elite. “Howev- From the right, the Palace of Justice OF ASYNCHRONICITIES er,” Michalsky adds, “everyone, abso- thrusts itself like a limestone gray bar lutely everyone, throws a coin into the in front of an entire city district. These places of retreat span the city like basin to make a wish for the future and Tanja Michalsky steps onto the ter- a cobweb. Has anyone ever recorded to make sure they will return to this race of the Bibliotheca Hertziana and them on a map? Has anyone recog- place one day.” lets her gaze wander. To the left, in the nized them as a further layer, high It is precisely this juxtaposition of south, the monumental column struc- above the places that have sunk and asynchronicities, the researcher ex- ture of the national monument to been buried, the antique, medieval and plains, that not only determines the Vittorio Emanuele II towers over a for- the modern, the commercial and repre- feel of the city, but also provides the mer empire. It is a temple built accord- sentative levels of life? They would tell topic and direction for her work. “Here

ing to the Greek model and is less than of warm evenings under the stars, of in Rome, art didn’t have to invent Photo: Bernd Wannenmacher

74 MaxPlanckResearch 2 | 19 Photo: Bernd Wannenmacher unknown regions. unknown into research history art taking is TanjaMichalsky direction: Own

76 which toexplorethetombs ofthe 1990s, sheusedRomeasa base from in RomeasitsDirector. Duringthe Max-Planck-Institut für Kunstgeschichte tered bythearthistorian. lected foralongtime.Allthisisregis- loud, and the garbage hasn’t been col- moves tortuouslythroughthecity, it’s life is banal,eveninRome.Thetraffic says Michalsky, “aToyota.” Everyday for their car. ACinquecento?“No,” rently intownbuyinganewbattery eval andearlymodernperiods,iscur- specialist inItalianartfromthemedi- at theFreieUniversitätBerlinanda Klaus Krüger, Professorof Art History cowed. Sheaddsthatherhusband, from allowingthemselvestobeeasily new anddifferentwayshouldrefrain ina Anyone whowantstotellastory she hasadirectmannerabouther. her lightblondhairiscutshort,and hind it?Shewearsjeansandflatshoes, accent have? Is there an intention be- region. Whatmeaningdoessuchan that shecomesfromthe“Ruhrpott” burg, andoccasionally, youcanhear sight oftheothers. on oneleveloftime,toavoidlosing to definecontexts.Andwitheachstep to lay downpaths,to follow trails,and needs tices ofhercraft is that everyone in relationtothestructuresandprac- already there!”Whatemergesfromthis search. “Therewas somuchthatwas explaining thestartingpointforherre forthefirsttime,”shesays, everything MaxPlanckResearch 2 MaxPlanckResearch Tanja Michalsky grew up in Duis- Three years ago, she returned to the Three yearsago,shereturned tothe | 19 - great materialforhersubject field.The do, MichelangeloorRaphael, wereall dawn beingheroicfiguressuch asLeonar era, andtheprotagonistsof thisnew gnon in the early 15 popes, theCuriareturningfromAvi torian givesherroutineanswer. The nealogy. Purepowerpolitics.” reinforcing andsecuringone’s ownge- of the Middle Ages focuses mainly on their concerns! The memorial culture –thatwastheleastof from purgatory’ “This hadnothingtodowith‘saveme puzzle together, she had a solid result: detective workputtingthepiecesof time shehadfinishedherinvestigative must haveenjoyedthework.By witness toapoliticalsituation?”She what makesatombsuchanimportant in herowncasual,trenchantway. “And scribing themainfocusofherproject from pasteras?”shesays,bywayofde- “How doyouinterpretstrangeartifacts POLITICS, NOT PURGATORY THIS HAD TO DO WITHPOWER ported cultures. interactions betweenlocalandim ples, and to identify the complex ending chainofforeignrulersNa- eval Frenchdynastyinthesheerun- inscriptions inordertolocateamedi stone platesanddecipheredweathered tation. Shescratchedtheearthfrom An at largethebeginningofanew, refined an urgentneedtopresent theworld gevin kingsinNaplesforherdisser And whatabouttheart?Thearthis- th century, who felt - - - - tute, whichwasfoundedin1913bythe successes oftheresearchers attheInsti talks ofappropriationsantique cul- with thenames.”Forthisreason, she Unfortunately, we arenotsofamiliar name justthemostimportant ones. Renaissance duringthe13 a CarolingianRenaissanceand another in Romeexplains.“Therewereseveral: naissance,” theDirectorofInstitute man Nation. nota bene–RomanEmpireoftheGer – a of to presenthimselfastheemperor tiquity andreferred to themin order quoting ideasandexamplesfroman- form! Even Charlemagne was already pled severalmyths.Notetheplural top Western1960, Art”,publishedin “The RenaissanceandRenascencesin art historians.Hisgroundbreakingbook himself issomethingofaheroamong Panofsky,And shereferstoErwin who waiting tobefinallykissedawakeagain. tants, a great city of years gone by field ofrubblewithalmostnoinhabi- a thousandlongyears,thatitwas she claims,thatRomelaydormantfor work inanewdirection.Itismyth, roque painterCaravaggio. were falselyascribedtothegreatBa- world fromafloodofpaintingsthat sor, SybilleEbert-Schifferer, savedthe it isn’t thatlong agothatherpredeces- architecture of theBaroqueperiod.And the Renaissance,illustriousartand lar –coveringantiquity, theheroesof patron HenrietteHertz,werespectacu- “There wasinfactnotjustoneRe- Yet Tanja Michalskyissteeringher th century, to - - -

Photo: Enrico Fontolan/Bibliotheca Hertziana CULTURE & SOCIETY_Personal Portrait

Best outlook: the roof terrace of the Bibliotheca Hertziana opens up a view over the rooftops of Rome, with the cupola of the San Carlo al Corso church (left), the national monument to Vittorio Emanuele II (white monumental building, center) and the cupola of St. Peter’s cathedral (right).

ture – and by this, she means the tech- of Italy, and to connect all this with the niques and results of the appropriation, present day. Tanja Michalsky loves tak- rather than a historical event. The stat- ing the discussion forward to as yet un- ues and buildings from antiquity were known regions, where there are new already there, after all. They were part discoveries waiting to be made. of everyday life. Anyone could observe As a result, the desk in her office is and study them. And many people did now full of medieval city maps. On the just that. bookshelf behind it, there are DVDs In other words, more Middle Ages. with classic films by Fellini or the enig- More present-day. And a greater aware- matic levels of reality created by David ness of the migration of people and Lynch, that are layered like gossamer- culture, of the multifaceted links be- thin films. In “Lost Highway”, the mys- tween the Italian south and the rest of terious expedition into film as a medi- Europe and the world, which she expe- um, hunted by dark fantasies, the art rienced in such concentrated form in historian sees a model for research in Naples. Anyone who wants to study her own field of activity. From Rome, the history of a city, the ultimate em- colleagues explore the face of Europe bodiment of urbanity, must be pre- beyond Europe, reconstruct the global pared to peel away one by one the network of Italian art since the early many layers it contains, to filter all the modern era, and seek out the mutual ingredients of this amalgam and to re- exchange between directors and pro- construct the way they fit together: An- ducers from the Cinecittà film studios. gevin tombstones and Greek columns, And through all this work, they come Goths, Hohenstaufen, Spanish and considerably closer to the complex na- Bourbons, national monuments and ture of this city. roof gardens. She has spent long The layers of urban life, the links be- enough scraping away at these hidden, tween eras and cultures, the open and overgrown, weathered links. And the hidden motifs of any reduction of real- Source of longing: since Federico Fellini same principle applies to Rome as it ity... Was it not wonderfully ironic that immortalized the Fontana di Trevi in does to all cities. half an hour previously, the journey to his film “La dolce vita”, with Anita Ekberg and Marcello Mastroianni, the fountain That’s why, together with Tristan the Institute on the Pincio on the edge has become one of the major tourist Weddigen, the second Director of the of the inner city already gave an indi- attractions in Rome. Bibliotheca Hertziana, she decided to cation of the complex interplay be- expand the Institute’s program to cover tween reality and fiction? Rome is built

Photo: Enrico Fontolan/Bibliotheca Hertziana Photos: picture alliance/KEYSTONE (center); averess/Alamy stock photo (below) earlier eras and places beyond the south on hills, and some roads wind uphill in

2 | 19 MaxPlanckResearch 77 CULTURE &SOCIETY_PersonalPortrait 78 “orientation”. term the hence – orient the towards eastwards, directed was view the time, that at that things other among shows around drawn Rome of map the map: informative An the maphadpaidforthismanipulation The people whopublished hire service. to markoutabar, apizzeriaormoped built-on areas,therewasenoughspace the uniformlightredcolordepicting the proportionsweredistorted.Yet on rectly placed, even for larger roads, and Junctions andcrossroadswereincor- many narrowstreetsandpassages. and thisiswhereyouwanttogo. two crosses on it: this is where you are, maps designedfortouristsandmarked hotel tookoutoneofthosehandycity Thehelpfulporterinthe broad curves. MaxPlanckResearch 2 MaxPlanckResearch However, themapdidnotshow 700 years ago by Paolino Minorita | 19

doctoral qualification period, which is painting as part of her extended post- an sinceshestudiedDutchlandscape a subjectofinterestforthearthistori- a constantlychangingworldhasbeen appears.Therepresentationof century Paolino Minoritafromtheearly14 terrace. AmapoftheCityRomeby her office,afewfloorsbelowtheroof she says,andopensupthecomputerin Tanja Michalskyhastolaugh.“Look,” OF REALITY EVERY MAPISANABBREVIATION generate turnover. Isn’t thatappalling? tion points,buttoseekoutshopsand through thecitywithoutanyorienta- tourists werenotencouragedtowander And, ascouldbeseenfromthemap, of realityfromtheiradvertisingbudget.

ship. Andthecartographicsystemsof required forafulluniversityprofessor- the reason is a bad one, and sometimes, the reasonis a bad one, and sometimes, tion is made for a reason.” Sometimes, says, insummary. abbrevia- “Andevery map is an abbreviation of reality,” she um, theerrorsandtemptations.“Every atic distortionsinherenttothemedi time, thescientistwarnsagainstsystem just onemap.However, atthesame centi which isaccuratedowntothelast view throughtoaGPSsatelliteimage er attemptsatcreatingabird’s eye data, progressinabstractionandearli place onthebasisofitstopographical growing abilitytorecordanddepicta this world. symbols are one way of documenting it issimplyblandcommercialism. From theconquestofspaces, meter meter – allthiscanbereadfrom - - -

Paolino Minorita: Cronologia magna, Venice, Biblioteca Marciana, Lat. Z. 399 (=1600), fol. 98. Paolino Minorita: Cronologia magna, Venice, Biblioteca Marciana, Lat. Z. 399 (=1600), fol. 98.

Photo: Marieke von Bernstorff pear tobeafinalstatement oftruth. the roofterrace.Allconnections ap knowswhere itis. Everyone Steps. It’s impossibletoloseyourway. ed at the upper end of the Spanish with abadmap.TheInstituteislocat- difficult tofindyourwayaround,even ent –hencetheword‘orientation’.” was directed eastwards, towards the ori- tury,” sheexplains.“Before, theview came aboutmuchlater, inthe17 image oftheworldtonorthonly tion: “Thehabitofalwaysorientingour ever, sheisquicktoprovideanexplana runs horizontally over themap.How- through the cityin the familiar way, it stead ofwindingitswaysouthwards wide river, whichisclearlytheTiber. In cus, is not that great.It’s nice to see the ly bringstheadvertisingtargetsintofo- road mapofthepresent,whichbrazen- develop amedievalcomputerapp. texts,asthoughhehadwantedto tory er representation levels using explana- linked thetopographicalanchor to oth ofthecity.telling thestory Paolino placehasaroletoplayin and every thor presentedadramaticcomposition, recorded here700yearsago.Theau as though it were her present that was tist’s fingermovesswiftlyoverthemap imagination, the Colosseum. The scien gelo andwithacertainamountof umned portal,as is theCastelSant’An- recognizable fromitsclassicalcol- streets andaqueducts;thePantheonis the lateMiddleAgesdrewanetworkof ownstoriestotell. very ofcartographyhasits else! Thehistory formation. Ofcourse,theSwiss,who sure fromsuchchoicenewitemsofin- out whereitcamefrom.Shegetsplea- Tanja Michalskygrinswhenshepoints altitude linesoriginatedinSwitzerland. drawing themonamapthebasisof familiar perspective.Themethodof when viewedfromabovethanthe different peaks andridgeslookvery before therealizationtookholdthat since itwouldbeanotherfewcenturies city’s hillsonhismapasalateralview, an honestman.Heevenregisteredthe This PaolinoMinoritawouldhavebeen The cartographerofRomeduring All thiscanbeseenfromabove on Incidentally, itwouldnotbeatall The differencebetweenthisandthe th cen------of planningandbuildingthe library. decessors hadenduredthestressful task had beencompleted. Her pre- erything book everleavesthebuilding. Never. rule applieswithoutexception thatno ful, relaxedconcentration.Afterall,the times. Thereisanatmosphereofcheer- ture. Thereareresearchers thereatall workspaces layeredinaterracestruc collection,and90generous history documented photographsfromtheart and around 870,000carefullypreserved volumes, the 360,000orsolibrary road, butitisspaciousenoughtohold surrounding the16 60 B.C.,inthemiddleofensemble and hostLuciusLiciniusLucullusfrom commander military of thelegendary building there,exactlyabovethegarden Juan NavarroBaldeweginsertedanew Eight yearsago,theSpanisharchitect CONCENTRATION PREVAILS AN ATMOSPHERE OFCHEERFUL research asthough throughafunnel. into themachineroomsofarthistory the widehorizonofcityanddown to turnaroundshifthergazefrom of totalrepresentation.Sheonlyneeds their fantastical,unrealizableconcept which Eco,BorgesandEndespread Tanja Michalskyreferstothemapsover Zuccari. Itcannotbeseenfromthe city maps and contemporary feature films as part of her research. her of part as films feature contemporary and maps city medieval studies TanjaMichalsky research, her in eras: different of view A The newDirectorarriveswhen ev- th century Palazzo Palazzo century - means oftransportationfora story. this meansthattheyarealways the tographs, too,arestillonlyimages. And sion of satellite location, since their pho- tion.” Andshewarnsagainst thepreci- create spaces. Their neutrality is a fic- bing in.AsTanja Michalsky says:“Maps his timewerestillonlyhesitantlydab- was somethingthatthecartographersof did realizethatitwasAmerica,which while hedidnotdiscoverAmerica, pucci. Thehistoriographerwrotethat ian merchant andseafarerAmerigoVes with hisbiographicalsketchoftheItal- brary, butwedohaveone.” to false expectations: “We arenot a li- her Institute,whichoccasionallyleads quietly strugglingwiththenameof must conductresearch,” shesays,while might onedaybeinadequate.“We generous spaceallottedtothedepots ders. Sometimes,sheisworriedthatthe edge cannolongerbedefinedbybor- Science andthemovementofknowl Institut fürKunstgeschichteinFlorence. also emerging with the Max-Planck- change. Newlevelsofcooperationare promoting meetingsandinitiatingex- layer bylayer. Expandingherhorizon, of art and culture ering the history most no distractions: carefully uncov- tual purposeoftheInstitutewithal- is. Shecanturnherattentiontotheac- The scholarknowshow fortunate she She has just re-read Stefan Zweig, She hasjustre-readStefanZweig, 2 | MaxPlanckResearch 19MaxPlanckResearch

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FLASHBACK_Aerodynamics

A method that lends wings

Mathematician Irmgard Flügge-Lotz was one of the first female researchers in the field of aerodynamics and automatic control. While working at the Kaiser Wilhelm Institute for Flow Research, she succeeded in simplifying the calculations required for aircraft construction. Flügge-Lotz was later appointed the first female Professor of Engineering at Stanford University. In the U.S., her work is still held in high esteem. In Germany, however, she has been all but forgotten.

TEXT KATJA ENGEL

Goettingen, 1931. Leading flow researcher could only be tested by means of complex Ludwig Prandtl was astonished. His colleague, wind tunnel measurements. Ludwig Prandtl, at 28 just half his age, had just handed him who is generally thought to be the founder of the solution to a mathematical puzzle that no- aircraft aerodynamics, and his team in Goet- body had been able to crack for more than ten tingen carried out pioneering work on the years. This conundrum was on his “menu”, as theoretical description of lift. However, math- he called his list of uncompleted research ematical calculations of his wing theory tasks. The result went down in the history of turned out to be difficult. In 1919, Albert Betz, aerodynamic research together with the a doctoral student in Goettingen who was young researcher's name. The "Lotz method" later to become Prandtl’s successor at the In- makes it possible to calculate the lift on an air- stitute, finally succeeded in the describing lift plane wing with comparative ease. by means of differential equations. However, Prandtl soon made the woman who had so his formulae were too complex for practical impressed him an (unofficial) Head of Depart- use when constructing new profiles. Expen- ment at the Aerodynamische Versuchsanstalt sive wind tunnel testing was still required to » (AVA, now the German Aerospace Center), part show the aerodynamic flow around various A model teacher and researcher: of the Kaiser Wilhelm Institute for Flow Re- wing shapes and determine when turbulence Irmgard Flügge-Lotz was popular with search in Goettingen. This marked the start of colleagues and students alike. would occur. Moreover, reckoners with slide Irmgard Lotz's career as an internationally rules would have to spend days solving the renowned aerodynamics expert and control equations – at that time still traditionally a engineer. Yet before 1960, when she became the first female Pro- woman's task. In all, the procedure was unserviceable for pur- fessor of Engineering at Stanford University, her scientific career poses of practical aircraft design. was anything but meteoric. For more than ten years, mathematical descriptions were the Irmgard Lotz was born on 16 July 1903 in Hameln. This was the biggest obstacle standing in the way of the practical application year in which the Wright brothers in the U.S. set a milestone in of wing theory – until Irmgard Lotz developed her method of cal- the development of aeronautics. Working in a wooden shed, the culation and astonished Prandtl. “An expert reckoner can calcu- two bicycle mechanics built their “Flyer”, one of the first motor- late the necessary odd and even coefficients […] in just 2 ½ hours,” ized aircraft that was really capable of flying. This was another she wrote in the Zeitschrift für Flugtechnik und Motor step forward in the development of the airplane, which at that luftschiffahrt, the journal which published her method. It was time was progressing with impressive speed. However, this was the long-sought solution that closed the gap between theory and still the era of inventors. There was one thing that these bold pi- practice. Engineers were now able to calculate the requirements oneers of the skies did not manage to do: they were unable to ex- for better-performing wings before the construction work began. plain the mysterious forces that enable an aircraft to ascend de- Prandtl’s appointment of Irmgard Lotz in 1929 as the only spite being several thousand kilograms heavier than air. woman in his team of 25 at the AVA paid off. This was not a new While aeronautic research was also making rapid strides by situation for her. She was the only woman at the Technical Uni- the end of World War I, these advances were more theoretical in versity of Hanover to be awarded a doctorate in applied mathe-

nature. Wing profiles – a major factor in aircraft construction – matics. She rejected a job offer from the steel industry. Irmgard Photo: Stanford Library/Stories from the Archives

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Lotz had known that she wanted to help realize humankind's dreams of flight right from her childhood, when she had watched the huge zeppelins taking off from close by. She later recalled a resolution she had formed before going to university: “I wanted a life that would never be boring. That meant a life in which new

things would always occur.” A breezy testing ground: the flow around wing profiles was Shortly after her appointment to the Kaiser Wilhelm Institute, tested in the wind tunnel in Goettingen – until the Lotz method the barely 30-year-old mathematician was put in charge of a made this possible with simple calculations. group of scientists and female mathematicians. Irmgard Lotz became one of the few female Heads of Department at the Kaiser Wilhelm Society, albeit only unofficially. After developing the and Irmgard Flügge-Lotz, who moved to the Office national "Lotz method", she worked on other mathematical solutions for d'études et de recherches aérospatiales. Here they worked on equal the field of aerodynamics. Then in 1937, Prandtl nominated the terms as research group leaders. talented woman for the post of research professor and submit- Although they were both happy in Paris, they lacked opportu- ted the corresponding application to the Reich Ministry of Avia- nities for career advancement. In 1948, they contacted Stanford tion. His letter listed 13 of her publications. However, the appli- University in the U.S., where Wilhelm Flügge was subsequently cation was rejected. The Nazi regime did not approve of women appointed professor. For Irmgard Flügge-Lotz, however, the move in leading positions. was a step backwards, as she merely received the post of lectur- In 1938, Irmgard Lotz married civil engineer Wilhelm Flügge er – the lowest rung in the university hierarchy. The rules at and took the name Flügge-Lotz. Disheartened by being rejected Stanford only allowed one half of a married couple to work as a for the post of research professor, she followed her husband to professor at the university. Berlin-Adlershof that same year. He accepted a position as However, this did not stop Irmgard Flügge-Lotz from carrying out a professor’s tasks in the fields of teaching and research. THE NEW YORK TIMES of May 23, 1974 She gave lectures and seminars, supervised doctoral students and moved ahead with her research – in both flow mechanics The author of more than 50 scientific papers, including and automatic control. Students and colleagues alike found it a 1931 computation on wing lift that contributed to modern » more and more difficult to understand why the “lecturer” was aircraft design, Professor Flügge-Lotz had been working not a “professor”. The same question was asked in summer 1960 in retirement on problems of satellite control, heat transfer in an international setting when Flügge-Lotz became the only and drag of fast-moving vehicles. female delegate from the United States to attend the first con- gress of the International Federation of Automatic Control in Head of Department at the Deutsche Versuchsanstalt für Luftfahrt Moscow. Shortly afterwards, Stanford University appointed her (German Aeronautical Research Laboratory – DVL). She was to the post of ordinary Professor of Engineering Mechanics, obliged to stay in the background and obtained a post as a Aeronautics and Astronautics. “scientific advisor for aerodynamics and the dynamics of flight”. The remarkable scientist indefatigably continued her research Flügge-Lotz made the most of her time and did the groundwork and teaching activities over the years that followed. Even after she for one of the first standard textbooks on discontinuous control. retired in 1968, she remained active in the field of research and re- One contemporary researcher called it “a groundbreaking contri- ceived numerous honors. The American Institute of Aeronautics bution to automatic control theory” – a subject that was still in and Astronautics elected her a Fellow – the first woman ever to its infancy at the time. receive this accolade. The Society of Women Engineers presented However, Irmgard Flügge-Lotz and Wilhelm Flügge did not her with their Achievement Award, and the University of Mary- stay in what was then the capital city for long. Actions taken by land awarded her an honorary doctorate. Only in Germany has she the Nazis led to World War II, and in 1940 the first bombs fell on been practically forgotten. Berlin. By the time of the heaviest Allied bombing raids in Febru - On her death in Palo Alto, California, in 1974, a brief obituary ary 1945, the couple, along with part of the DVL, had already was printed in the New York Times. And in 2014, almost 40 years moved to Saulgau north of Lake Constance, an area that was less later, Stanford University paid posthumous tribute to her as one at risk. This meant that after Germany capitulated, they found of 35 “Engineering Heroes” who had been the driving forces be - themselves in French occupied territory. The French enticed hind the human, social and economic progress made through

Photo: Stanford Library/Stories from the Archives Photo: Archive of the Max Planck Society, Berlin-Dahlem many researchers away to Paris. They included Wilhelm Flügge technology and science.

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Joining the Square Kilometre Array

Max Planck Society becomes newest member of SKA Organization

The Max Planck Society has become the crucial pre-construction phase,” the The Max Planck Society is a non-profit 13th member of the SKA Organization, Chairwoman of the SKA Board of Direc- organization with 84 Institutes and re- following an unanimous vote by the tors, Dr. Catherine Cesarsky, explained. search facilities. In collaboration with SKA Board of Directors. The decision to German research institutions and other German institutions and indus- accept the application for membership industry have been an intrinsic part of try, it has been involved across many was taken at the 29th Board meeting at SKA-related projects since its earliest areas of SKA design work, including the SKA Organization Global Headquar- days, and make a significant contribu- within the Mid Frequency Dish Array, ters in the UK. tion to ongoing SKA design activities. Low Frequency Aperture Array, Central The Max Planck Society joins the fi- In particular, the Max Planck Society Signal Processor, Science Data Proces- nal phase of the SKA Organization, provides instrumentation in the form sor, Telescope Manager, Signal and Data which is overseeing the telescope design of detectors, data acquisition and anal- Transport consortia, and research and phase, until the process of transitioning ysis systems for South Africa’s world- development work within the Phased into the SKA Observatory, an intergov- class MeerKAT telescope, an SKA pre- Array Feeds and Wideband Single Pixel ernmental organization (IGO) estab- cursor facility which will become part Feeds consortia. lished by treaty to manage the construc- of SKA-Mid. One of the Max Planck Society’s In- tion and operation of the SKA, is com- “I am extremely pleased to see our stitutes is the Max Planck Institute for pleted. Any further German involve- German colleagues consolidating their Radio Astronomy (MPIfR), a key player ment through participation in the SKA long-lasting involvement in SKA-relat- in the SKA’s Dish engineering consor- Observatory remains to be decided and ed activities both at a scientific and tium. Together with German industry will be the subject of future discussions. industrial level,” added Prof. Philip partners, such as the telescope antenna “I am delighted to welcome the Max Diamond, SKA Director-General. “Ger specialists MT Mechatronics (MTM), Planck Society to the SKA Organization many’s great wealth of expertise in ra- and international partners, the Dish as our 13th member, a deserved recogni- dio astronomy, both in science and consortium is responsible for designing tion of the significant contributions engineering, will continue to be invalu- the SKA’s mid-frequency array (SKA- Germany has made to the SKA project able as we move ever closer to SKA con- Mid), to be deployed in South Africa, over the years, and particularly in this struction and operations.” The Dish consortium has already delivered two prototype SKA dishes: SKA-P, which is currently being tested in Chi- na, and SKA-MPI, funded by the Max Planck Society, which is under construction on the SKA site in South Afri- ca’s Karoo region. “The SKA is a great opportunity for astronomers, engineers, physicists and data scientists. Besides becoming an amazing discovery machine, SKA push- es the boundaries of what is technical- ly possible, especially in the handling and analysis of huge amounts of data. The Max Planck Society is at the center of all these exciting science and technology developments, and we are pleased to now be able to contribute officially to the SKAO efforts,” says Prof. Michael Kramer, Director at the MPIfR.

The Max Planck Society has funded a second SKA prototype dish, SKA-MPI, currently being constructed on site in South Africa, bringing together Chinese, Italian and

German components. Photo: South African Radio Astronomy Observatory (SARAO)

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Photo: MPI of Molecular Cell Biology and Genetics Remembering Suzanne Eaton The Max Planck Society mourns the death of an exceptional scientist exceptional an of death the mourns Society Planck Max The ly, Suzanne’s research focused on the interaction of of interaction the on focused research Suzanne’s ly, recent Most tissues. in distances long over spread are signals how explain to able was team zanne’s Su and interactions, properties physical and their of the morphogens, signaling discovery molecules, the Through tissue. form to other each with cate approaches to understanding how cells communi groundbreaking and new discovered she ativity, and cre curiosity to insatiable her league.” Thanks inwas with following “Suzanne her own statement conception,” writes the Board in of Directors their at since the its MPI-CBG the research characterized and as such that inspired has the interdisciplinarity – mathematics and physics biology, – disciplines different bridged she that in Institute our of ment tissues?” form cells do “How question the was research her of focus The fly. fruit the of development the in formation pattern the for explanations deeper find to order in laboratory own her in research of areas distant seemingly In Dresden. of versity of Center the at Technical the Uni- Biotechnology and a Professor and Genetics, Biology Cell lecular Mo of Institute Planck Max the at Leader Group Research beginning. very its from right Dresden in Institute the of pillar essential an person, key a been had Eaton that saying human being, and a wonderful scientist outstanding an as Eaton to paid Suzanne tribute Stratmann Martin President Planck Max Hyman, Tony band, hus her to letter personal a In 2,July on 2019. Crete in end tragic a to came life whose Eaton, Suzanne of death the mourns Society Planck Max The pathways. metabolic signaling and “Suzanne had a huge impact on the develop the on impact huge a had “Suzanne Senior was Eaton Suzanne 2001 , she started linking started she , - -

Suzanne Eaton Suzanne - - - - - www.mpi-cbg.de/institute/remembering-suzanne friends and colleagues: family, from Eaton Suzanne of legacy and life the to tributes collected has Genetics and ogy Th scientist. brilliant a and friend, and colleague tic lively,We creative, enthusias miss a wonderful, succeed. to able being of th them giving research, own their develop to ties universi top from Dresden to coming welcome feel leaders group young of generation first the made she personality, steady and calm her With player. piano enthusiastic and athlete, mother, scientist, of roles many her combine to balance perfect the found She science. in career a with full the to lived life a balance to possible was it to that be no doubt innovative her,For seemed ideas. there for room of plenty with ronment family-friendly,international,envi- intellectual a as community this on influence decisive a had Eaton Suzanne Institute. of opment the Dresden e feeling e of feeling having come to the right place and e Max Planck Institute of Molecular Cell Biol She was instrumental in shaping the devel the shaping in instrumental was She in the wider scientific commu scientific wider in the international impact immense an had work scientific her and research, of field her in player Eaton was a Suzanne key selves: them for speak journals ing high-rank in publications her mechanisms, biological mental funda uncovered studies Her for early career researchers. researchers. career early for environment excellent an and science of beacon a as world the throughout known Dresden, of city the and Genetics, and Biology Cell Molecular of tute Insti Planck Max the making in part big a played She nity. MAX PLANCK COMMUNITY MAX PLANCK 2 | MaxPlanckResearch 19MaxPlanckResearch ------83 MAX PLANCK COMMUNITY

Max Planck survey on work culture and atmosphere

The findings show that the principles of scientific action must be complemented by the principles of cooperation

In February 2019, the President of the degree of individual commitment less support in their careers. Among Max Planck Society, Martin Stratmann, and within their respective work the main target groups of mentoring, commissioned a science-based Max- units are bound by a strong shared doctoral candidates and postdocs, Planck-wide survey on working culture vision and collegiality. only one in two respondents agreed and working atmosphere. The findings with the statements in the survey re- are now in. “We wanted to get an idea l About 80 percent of the respondents garding career development support. of the mood across the whole organiza- say that individuals with leadership tion and create transparency for coop- functions have a high employee focus l Based on their own estimates, non- eration and leadership culture at the and are willing to support a dynamic scientific staff (11.8%) were subjected Max Planck Society,” Martin Stratmann change culture. This is particularly the to bullying significantly more often explains. “The results show how impor- case for scientific staff members. Non- during the 12 months of the survey tant it is to continue to build a perfor- scientific staff view the change culture than scientific staff (7.5%). mance-oriented but also a respectful slightly more critically. In particular, and appreciative working culture and they are less likely to confirm that CARRYING OUT THE STUDY atmosphere at our Institutes and to in- they feel respected by their superiors. troduce measures for changes at the rel- In order to guarantee the neutrality, evant locations.” l In the last 12 months, around 10 per- data protection and especially the sci- The study was implemented by a recent of respondents stated that they entific quality of the project, a research search team from the Fraunhofer Insti- had experienced bullying at the work- team was set up at the Center for Re- tute for Work Organization headed by place based on their own understand- sponsible Research and Innovation at Prof. Dr. Martina Schraudner. More ing. This is an average result com- the Fraunhofer Institute for Industrial than 9,000 employees of the Max pared to recent international studies. Engineering IAO (CeRRI) under the di- Planck Society, which represents 38 per- During the same period, 3.9 percent rection of Martina Schraudner. The sur- cent of the entire workforce, took part of all respondents stated that they vey‘s sample size is the largest, in abso- in the survey. The study is unique in had at least occasionally experienced lute terms, of any investigation of a sin- this form, because for the first time, the sexual discrimination, which is below gle scientific organization. questionnaires was not only sent to the international average. The current The survey is highly representative doctoral candidates and postdocs, but report by the U.S. National Academies because the sample size makes up a also to all scientific and non-scientific of Sciences, Engineering and Medi- very good proportion of the total. staff. The topic of bullying was also in- cine, for example, gives a figure of “Compared to researched studies, a vestigated, after public reports in 2018 20 percent in this area. globally unique data set regarding had referred to allegations at two Max sample size, details and thematic Planck Institutes. l Deficits are identified in relation to scope was collected on work condi- mentoring by direct superiors. Wom- tions in cutting-edge research,” Martina THE FINDINGS AT A GLANCE en in particular feel that they receive Schraudner emphasizes.

The uniqueness of the data set provides a benchmark in the generally poorly researched environment of the work conditions in cutting-edge research.

l The staff members of the Max Planck Society demonstrate a high level of commitment to the organization,

i.e. they are willing to display a high - + Graphic: Shutterstock

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Wolfgang Baumeister wins the 2019 Stifterverband prize

The biophysicist has revolutionized molecular structural biology with the help of cryo-electron tomography

In contrast to our knowledge of our planet, there are still many unexplored regions in the cellular nanocosmos. The fragile architecture of large protein complexes composed of numerous subunits is particularly difficult to decipher. This is because attempting to isolate and purify the proteins also rips them out of their functional context. Wolfgang Baumeis- ter has been pursuing a completely new approach for more than three decades. The Director at the Max Planck Institute of Biochem istry has developed a method that opens up entirely new possibilities and numerous fields of application for structural research: cryo-electron tomography. He is now being recognized with the Wissenschaftspreis des Stifterverbands 2019 (Science Award of the Donors’ Association) for his pioneering work. The prize, which is endowed with 50,000.00, was awarded by the Max-Planck-Gesellschaft (MPG) and the Stifterverband at the annual MPG meeting in Hamburg on 25 June. Wolfgang Baumeister receives the prize in recognition of his outstanding achievements in the field of cryo-electron tomography. What is particularly notable here is his examina- Wolfgang Baumeister is awarded the 2019 Stifterverband prize tion of molecular and supramolecular structures within the for his cryo-electron tomography. The method opens up context of intact cells at high spatial resolutions. The jury ex- numerous application possibilities, including in electronics, plained that it was awarding the prize because of the method’s materials technology and pharmacy. great economic relevance, which is evident in important areas of high technology, such as electronics, materials technology and pharmaceuticals. The cryo method allows larger spatial electron tomography, he and his team have been able to de- structures from cells to electronic components to be tomo- cipher the structure of the 26S proteasomes, which are high- graphically captured at very high resolutions and analyzed. ly complex molecular shredders for proteins that are made “We are developing methods to make the molecular ar- up of 66 individual proteins. He and his team have also been chitecture of cells visible,” said Wolfgang Baumeister, sum- able to reveal the superior organization of the ribosomes in marizing his research focus. The cryo-electron tomography cells, the so-called polysomes. method that he has developed in conjunction with his team The researchers have now turned their attention to oth- opens up completely new opportunities for structural reer cellular structures and are investigating the blueprints search: entire cells or cell organelles are “shock-frozen” in of pores in nuclear membranes, contact points between liquid nitrogen in the blink of an eye. The fragile cell archi- nerve cells (synapses) and protein complexes in mem- tecture remains unchanged while it is embedded in the glassy branes and cell walls. It is possible to use cryo-electron to- ice. Two-dimensional images of the samples to be examined mography to image these macromolecular structures in the are taken from different angles. A three-dimensional image intact cellular environment. Pathological changes, such as is then built from these images. This method has already toxic protein aggregates that are mainly associated with made it possible to understand the architecture of many pro- such neurodegenerative diseases as Alzheimer’s and Parkin- teins in their cellular environments. son’s, may also be investigated in this way. This method, “It is only possible to understand the various functions which has been developed in basic research, is potentially for which the molecular machines are responsible by exam- able to open up new prospects for therapies by providing

Graphic: Shutterstock Photo: MPG / David Ausserhofer ining their structures,” explained Baumeister. Using cryo- insights into cell architectures.

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United with one voice

The Max Planck Society celebrates the inauguration of PostdocNet at Harnack House

The newly elected spokesperson of the PostdocNet initiative, Yu-xuan Lu, MPI for Biology of Ageing, at the inaugural event at Harnack House in Berlin at the end of April. The purpose of PostdocNet is to help forge links between all Max Planck postdocs.

PostdocNet – as ordinary members or as part of a working group – are encouraged to contact the group through the website or Twitter. Spokesperson Yu-xuan Lu takes a positive view of the work to be done: “We are delighted to have finally built a bridge between PhDnet and LeadNet, and the Max Planck Society will also benefit from PostdocNet as soon as it becomes easier to exchange questions and ideas.” The postdoc phase sets the course for a future career: while researchers en- PostdocNet was set up at the end of not only from the MPG, but also from joy increasing independence when April by postdocs from various Max PhD and other postdoc organizations,” planning, conducting and presenting Planck Institutes. This initiative will in explains Yu-xuan Lu from the MPI for their research and undergoing ad- future serve to improve links between Biology of Ageing, who was recently vanced training, they also have to as- all the Max Planck Society’s postdocs. elected as the PostdocNet spokesperson. sume more responsibility for supervis- Its primary goals are to provide post- The structure and statutes of Post- ing junior scientists and obtaining re- docs with support during their critical docNet are oriented on those of partner search resources. Moreover, this is the professional orientation phase and cre- organizations. As with PhDNet, it en- phase in which important career deci- ate a network for dialog. compasses the following working groups: sions are often made – for example In April, another element was inte- General Meeting, Secretary, Web/Media, whether to remain in academic science grated into the structure of the postdoc Seminar, Survey and Equal Opportuni- and research or to switch to business phase: PostdocNet. This is a grass roots ties. PostdocNet will also continue en- and industry. process that has already been attempt- gaging with working groups on the top- In order to help postdocs deal with ed several times at the MPG but is only ics of “Social Requirements”, “Scientif- the complexity of this career phase, now bearing fruit, due not least to the ic Requirements”, “Legal” and “Postdoc the Max Planck Society, with Chris- high fluctuation in postdocs and the in- Definition”; this last group has the sta- tiane Haupt (Human Resources Devel- tensity of the postdoc phase. “Staff at tus of an interim committee. opment & Opportunities Department) our Administrative Headquarters were Even though PostdocNet has made as the Project Leader, has put together already giving us hints and tips on or- great strides since the beginning of a postdoc package that includes struc- ganizing the start-up back in October 2019, there are still obstacles to over- tured guidelines and an extensive ad- 2017, and last year the President offi- come. Around half of all MPIs are cur- vanced training program. A conference cially gave us the green light, also with rently represented, and PostdocNet with the title “CareerSteps for Post- regard to financial support for our in- aims to forge links with postdocs at all docs” will also be held on June 6, 2019 augural event. We are very grateful for MPIs over the next year. All postdocs at the Max Planck Institute for Brain

the help that PostdocNet has received, who are interested in becoming part of Research in Frankfurt. Photo: Bettina Ausserhofer / MPG

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