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News from ICTP Spring–Summer 2018 14 5

News from ICTP:145

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The Abdus Salam International Centre for Theoretical 04 Delivers ICTP (ICTP) is governed by the United Nations Colloquium Educational, Scientific and Cultural Organization (UNESCO), the International Atomic Energy Agency (IAEA), and Italy. It is 06 2018 ICTP/ICO Prize Winner Urbasi a UNESCO category 1 institute. Sinha Promoting Quantum Science and Technology in India News from ICTP is a bi-annual publication designed to keep scientists and staf informed on past and future activities at 08 A Conversation with ICTP and initiatives in their home countries. The text may be reproduced freely with due credit to the source. 09 2017 Ceremony Honours Three Quantum Science ICTP on the web: www.ictp.it Pioneers Follow us on Facebook, Twitter, YouTube, Flickr, iTunes U, Instagram 10 Research Highlights

12 ICTP News Briefs

16 Alumni News

18 In Memoriam

ICTP Public Information Office Cover photo: Students from Palestine and Strada Costiera, 11 Morocco visited ICTP's SciFabLab in April to I-34151 Trieste learn how to use and code for 3D printers and Italy other tools, with the goal of opening fabrication laboratories at their home institutes. The students [email protected] were here thanks to a collaboration between ICTP, the Sunshine4Palestine non-governmental ISSN 2222-6923 organization, and the Young Minds section of the European Physical Society. 4 Features

Kip Thorne Delivers ICTP Colloquium

From winning a physics to developing the talk’s abstract outlines. Thorne described what these concept for a Hollywood blockbuster film, theoretical have begun to teach us, and ofered a vision for the Kip Thorne’s expertise and enthusiasm future of geometrodynamics. for astrophysics has captured the minds and imaginations of millions. His research in gravitational Professor Thorne is currently the Feynman Professor waves contributed to their detection by the of , Emeritus at the California Interferometer Gravitational-Wave Observatory (LIGO) Institute of Technology (Caltech). He was cofounder in 2015, and he lent his scientific credentials as a (with and ) of the LIGO consultant for the 2014 film Interstellar. project. LIGO - in the hands of a younger generation of - made the breakthrough discovery of On Thursday 24 May, Professor Thorne brought gravitational waves arriving at Earth from the distant his brand of science excitement to ICTP, where he on 14 September 2015. For his contributions delivered a colloquium on Geometrodynamics: The to LIGO and to research, Thorne Nonlinear Dynamics of Curved Spacetime. His talk shared the 2017 with Rainer centered on a challenge posed 50 years ago by Weiss and . In 2009, Thorne stepped his doctoral supervisor, John Wheeler, to explore down from his Caltech professorship to ramp up a geometrodynamics--understanding gravitation new career at the interface between art and science, through fluctuations in geometry--by asking, how including the movie Interstellar (which sprang from does the curvature of spacetime behave when roiled a treatment he co-authored, and for which he was in a storm; like a storm at sea with crashing waves? executive producer and science advisor). “We tried to explore this and failed. Success eluded us until two new tools became available: computer A video interview with Thorne is available on ICTP’s simulations, and gravitational wave observations,” the YouTube page.

5 Features

2018 ICTP/ICO Prize Winner Urbasi Sinha Promoting Quantum Science and Technology in India

In India, she created and leads the country’s first Back in India, Sinha’s lab is pursuing several research laboratory dedicated to research in quantum lines, providing valuable hands-on experience to optics, directing ground-breaking research in the many students who are keen to work with a quantum information and computing. Her research scientist of Sinha’s international stature. “Quantum achievements, combined with her active promotion information is a very new area in India, especially of optics research to the general public, have earned experimental, and ours is one of the first modern labs Urbasi Sinha the 2018 International Commission for to be dedicated to this field,” she said. One activity at Optics(ICO)/ICTP Gallieno Denardo Award. the lab is investigating a higher dimensional system--a unit of quantum information--called a qutrit. “This is an The optics prize is awarded annually to researchers alternative approach to trying to increase the number younger than 40 years of age from a developing of qubits in a quantum computer, which is what most country who have made significant contributions to the people are trying to do,” Sinha explained, referring to field of optics or photonics. Sinha was presented with technology giants like IBM and Intel who are in a race the award at a ceremony held at ICTP on 13 February, to produce quantum computers with 50 qubits. during the Centre’s annual Winter College on Optics. Other research lines include At her Quantum Optics Laboratory based at the Raman and . The latter, explained Research Institute in Bengaluru, India, Sinha has been Sinha, will play an important role in information security investigating new frontiers in the world of quantum once quantum computers become a reality. “The optics. Her experience in the field prepared her well for problem is that a quantum computer is going to be the pioneering role she now finds herself in. Educated able to run an algorithm which can break the classical at Cambridge, she spent several years at Canada’s key distribution, called Shor’s Algorithm, that is used Institute for Quantum Computing (IQC), where she was for encryption and decryption. So, we need a quantum encouraged by IQC Founder and Director Raymond answer to the question.” Laflamme (a student of ) to perform experiments in IQC’s quantum optics lab. “I wanted to learn quantum optics by experimentation, and this was one of the best environments to do that in,” Sinha explained. One of her first experiments there was to test a key concept of quantum mechanics known as Born’s rule (a rule that predicts the probabilities for occurrence of events) but had, until then, never been explicitly tested. The results of that experiment, summarized in an article with Sinha as lead author and Laflamme and others as co-authors, proved the validity of Born’s Rule and received broad media coverage after it was published in Science magazine in 2010 (10.1126/science.1190545).

6 Features

7 Features

A Conversation with Alan Guth

Guth has continued to elaborate the theory of inflation and delve into other topics as a professor at MIT. His three Salam Distinguished Lectures covered the possibility of our universe being part of a , the implications of eternal inflation of the universe, and the possible origin of the arrow of time. Work by Guth and other physicists on eternal inflation has led to the idea of a multiverse, where space is full of patches, with physical properties difering in each. “In most versions of inflation theory, inflation is eternal into the future— it stops in places, but always continues in other places. Where inflation stops, form, which we call pocket universes,” Guth explains. Increasing amounts of data are helping refine theories of inflation, but Guth The Salam Distinguished Lecture Series is an annual has said that it’s difcult to have a theory of inflation that tradition at ICTP, providing an opportunity for renowned does not lead to the existence of a multiverse. scientists to showcase recent advances in their fields. The 2018 series featured cosmologist Alan Guth, a Guth is still investigating the early universe in a variety professor at MIT and an ICTP Dirac Medallist. Guth of other ways. One of his lines of research is an explored fundamental questions about the beginnings exploration of primordial black holes, “which are black and structure of the universe in his ICTP talks. holes that could have formed immediately after the ,” Guth says. “We’re looking at a scenario where In 1979, Guth was a post-doctoral researcher the black holes form directly as a consequence of the focusing not on but on . density perturbations created by inflation.” Not much is He was in his eighth year as a postdoc, struggling known about how black holes merge and evolve over to find a job, when he heard two lectures by visiting time, but eventually, theories about primordial black cosmologists, one of which introduced him to the holes could provide predictions about distributions flatness problem. Our universe has no perceptible and masses of observable black holes today, providing space-time curvature, hence it is ‘flat’, a situation that more clues to the development of the universe. seemingly requires incredibly precise initial conditions. This leaves cosmologists to wonder how these initial “The amazing thing about the current state of conditions came to be so precisely fine-tuned. Guth cosmology is both how much we know and how was fascinated, even though it had little to do with his much we don’t know,” Guth says. “We know how previous work. It seemed suspicious that such precise to build inflationary models that make spectacular initial conditions would be just a coincidence. predictions for all the properties we can measure, like the measurements of the cosmic background radiation. Guth was soon drawn into cosmology and went on to Those measurements have grown more and more develop the theory of inflation. This theory describes an precise and still continue to fit perfectly with what exponential expansion-explosion of space from about simple models of inflation predict— I find that amazing.” 10-36 seconds to 10-33 seconds after the Big Bang, which Guth adds, “But at the same time, there are very accounts for the density distribution of the universe, the fundamental things that we don’t understand, so there large-scale structure of the universe. are some very important loose ends.”

8 Features

2017 Dirac Medal Ceremony Honours Three Quantum Science Pioneers

ICTP held its 2017 Dirac Medal Award Ceremony on the concept of the quantum logic gate and quantum 18 March 2018, honouring three pioneers in , as well as the network model of quantum sciences. Charles Bennett of the IBM Watson Research computations. He showed that all possible operations Center, of Oxford University, and on a quantum computer could be generated by Peter Shor of Massachusetts Institute of Technology combining sequences of a single kind of three-qubit were recognized for their groundbreaking work logic gate. (Later, Bennett, Shor and coworkers in applying fundamental concepts of quantum showed that sequences of one-qubit gates and mechanics to solving basic problems in computation one simple type of reversible classical two-bit gates and communication, bringing together the fields sufced.) of quantum mechanics, computer science, and information theory. Peter Shor boosted the field of quantum computation by designing efcient quantum algorithms for factoring Four decades ago, Charles Bennett independently large numbers and computing discrete logarithms, invented and carefully analyzed what is now known each of which can be used to break classical as reversible classical computation, proving that encryption schemes. He thus proved that a quantum classical computation can in principle be performed computer could solve a useful, hard computational without consumption of energy. With Gilles Brassard problem exponentially faster than any known classical (University of Montreal), Bennett invented quantum computer algorithm. Shor also introduced , where two distant parties share a secret error-correcting codes and fault-tolerant quantum encryption key, with security from eavesdroppers computation, which are schemes for coping with the guaranteed by the basic quantum limitations on efects of stray interactions (noise) disturbing qubits. measurements of incompatible observables. ICTP’s Dirac Medal is announced annually on Dirac’s David Deutsch is one of the founding fathers of birthday, 8 August, to scientists who have made quantum computing. He introduced the notion of significant contributions to theoretical physics. For a quantum Turing machine that would operate on more details about the prize and a list of past winners, arbitrary superpositions of states (that is, on qubits), visit the Dirac Medal web page.

9 Research Highlights Davide Bonadonna for MUSE - Science Museum, Trento, Italy Trento, MUSE - Science Museum, Davide Bonadonna for

ICTP researcher Federico Bernardini, in collaboration Research Team with an international team, have identified the world’s oldest lizard, providing key insight into the evolution of Including ICTP modern lizards and snakes. Their research appeared on the cover of the 30 May issue of Nature (doi. Uncovers World’s org/10.1038/s41586-018-0093-3). Oldest Lizard The 240-million-year-old fossil, Megachirella wachtleri, was originally found 20 years ago in the Dolomite Mountains, a UNESCO World Heritage Site in Northern Italy. Researchers originally thought it was linked to—but not an ancestor of—modern lizards and snakes. Further analysis by an international team of researchers determined the specimen was actually the oldest relative ever found of all living lizards and snakes, shaking up the evolutionary family tree of reptiles and shedding new light on the survivors of the most devastating mass extinction the world has ever faced.

The fossil was analyzed using high-resolution computer tomography at the ICTP Multidisciplinary Lab and Elettra synchrotron facility in Trieste. The three-dimensional digital images obtained allowed the researchers to look through the rock, at parts of the skeleton that were previously inaccessible, without damaging this unique fossil. This revealed a whole new suite of anatomical features that place Megachirella in a diferent and much more interesting light, indicating that it was actually older than previously estimated by at least 10 million years.

10 Research Highlights

Turning Entanglement A New Form Upside Down of Water

A team of physicists from ICTP and IQOQI-Innsbruck Water is liquid. Indeed, this is true at ambient has come up with a surprisingly simple idea to conditions, as experienced in our daily life. But investigate quantum entanglement of many particles. what would happen under extreme pressures and Instead of digging deep into the properties of quantum temperatures such as those inside planets rich in water wave functions--which are notoriously hard to like Uranus or Neptune? According to scientists, a new experimentally access--they propose to realize physical phase would appear, a form of water both liquid and systems governed by the corresponding entanglement solid: a “superionic” water. A team of researchers at Hamiltonians. By doing so, entanglement properties ICTP and SISSA, among which Sandro Scandolo and of the original problem of interest become accessible Erio Tosatti, already theoretically predicted this almost via well-established tools. This radically new approach 20 years ago in a study published in Science in 1999. could help to improve understanding of quantum matter Their paper was recently cited by a research team from and open the way to new quantum technologies. Lawrence Livermore National Laboratory (LLNL), the University of California, Berkeley and the University of Rochester, which has provided the first experimental evidence for the existence of superionic water. A recent note about the study, featured in Nature Physics, was posted by the New York Times last week.

“It’s the first time scientists have managed to recreate such extreme conditions in a lab, the only conditions under which to observe superionic water,” said Scandolo. He added, “Most of the credit for this result goes to the incredible technological development of recent years and to the cutting-edge facilities exploited. The confirmation of the existence of this form of water validates the theoretical and The team comprised ICTP researcher Marcello computational tools used to predict it.” Dalmonte (who also works closely with SISSA), along with and Benoît Vermersch from the Department of Theoretical Physics at the University of Innsbruck and the Institute of Quantum Optics and Quantum Information (IQOQI) of the Austrian Academy of Sciences. Their research, titled Quantum Simulation and Spectroscopy of Entanglement Hamiltonians, appeared in Nature Physics (doi: 10.1038/s41567-018- 0151-7).

Quantum entanglement forms the heart of the second quantum revolution. It is a key characteristic used to understand forms of quantum matter, and a key

resource for present and future quantum technologies. Commons Wikimedia from Roger McLassus (GFDL),

11 ICTP News Briefs

Physics Without Frontiers in Kabul ICTP Launches New Podcast ICTP’s Physics Without Frontiers programme has visited many places ICTP has launched a podcast! It’s called in the world, many multiple times as SciVibes, and it is now online for you to they gradually build communities listen to. This podcast brings you casual and networks of scientists. In April, conversations with global scientists, the programme visited Afghanistan fascinating chats that happen at cofee for the first time, meeting with over breaks and in the corridors with some of 400 eager students in Kabul at Kabul the thousands of scientists that visit ICTP University. An international team of every year. PWF scientists collaborated with local scientists and students to organize The coming conversations with scientists two days of a high-level workshop in will involve roman roads, paleoclimate particle physics and cosmology, with a techniques, career paths, the philosophy third day of outreach activities. of science, scientific capacity building, and quantum computing, among many other subjects.

You can find SciVibes on Soundcloud, iTunes, and Stitcher, and can listen to each episode on ICTP’s website at ictp.it/scivibes.

12 ICTP News Briefs

ICTP, KFAS Renew Commitment to Science

ICTP and the Kuwait Foundation for the Advancement of Sciences (KFAS) have renewed an agreement to provide support for scientists from Kuwait and the Arab world to participate in ICTP activities.

ICTP Director Fernando Quevedo and KFAS Director General Dr. Adnan Shihab- Eldin made the agreement ofcial in a signing ceremony at ICTP on 31 January. The renewed partnership continues KFAS support for ICTP postdoctoral fellowships, as well as for Arab students who have been accepted into the Centre’s Postgraduate Diploma Programme and for scientists from Arab countries to attend ICTP conferences and workshops. KFAS has also agreed to ‘Friends of ICTP’ to Strengthen continue its sponsorship of ICTP’s annual Bonds Amongst ICTP Salam Distinguished Lectures Series. Community In addition, the two institutes agreed to expand the partnership to new activities Since its opening in 1964, ICTP has related to scientific capacity building and hosted more than 180,000 visits of teacher training. scientists coming from 188 countries. To promote a bond of friendship and connections within this unique network, ICTP is happy to announce its support of ‘Friends of ICTP’, an association created to aid ICTP and its mission by developing international relationships through dialogue and cooperation among scientists.

Run by volunteers who have been associated with ICTP, Friends of ICTP strives to keep the spirit of ICTP founder Abdus Salam alive, through activities ranging from networking to mentoring to ofering a helping hand to visitors new to ICTP.

More information is available on the Friends of ICTP website (https:// friendsofictp.org/). Friends of ICTP President Joseph Niemela (left) with ICTP Director Fernando Quevedo at the signing of an agreement between the two organizations

13 ICTP News Briefs L. Scrobogna, ICTP Photo Archives ICTP Photo Scrobogna, L.

Victor Latorre Alberto Verjovsky

14 ICTP News Briefs

The Future of Quantum Technologies Salam Spirit Awardees Announced A new kind of computing is on the horizon, one that could greatly shift the way The family of ICTP founder and Nobel complex problems are solved. Quantum Laureate Abdus Salam has revealed computing, which until very recently was the winners of the 2018 Spirit of Abdus only theoretical, is slowly becoming a Salam Award. Announced annually on reality, promising a future of unprecedented 29 January—Abdus Salam’s birthday— computing speed. Major computer the award recognizes those who, like manufacturers such as IBM, along with Salam himself, have worked tirelessly search engine giant Google, are already to promote the development of science producing quantum computing chips that and technology in disadvantaged parts will someday drive a quantum machine. of the world. Quantum computing and technologies were the main topics of a public roundtable This year’s Spirit of Abdus Salam Award hosted by ICTP and SISSA on 14 March, recipients are Victor Latorre and Alberto honouring the work of its 2017 Dirac Verjovsky. LaTorre, a physicist from Medallists who received their awards at Peru, served on the Centre’s Scientific a ceremony earlier that day. The public Council as its first member from South roundtable featured three key players in America. His activities in his home quantum computing: country have influenced hundreds of Peruvian science students. Verjovsky ◃ Hartmut Neven, Google’s Director of is a mathematician from Mexico who Engineering has been highly influential in the ◃ Alessandro Curioni, IBM Fellow, Vice development of mathematics there. He President of IBM Europe and Director of enjoyed a close working relationship the IBM Research Lab in Zurich with ICTP founder Abdus Salam, ◃ Tommaso Calarco, Director, Institute for and convinced him that ICTP should Complex Quantum Systems, University establish a section in mathematics. of Ulm and member of the expert group for the European Commission’s Quantum Technology Flagship

15 Alumni News

Marlon Brenes of Costa Rica, a 2016 graduate of the joint ICTP-SISSA Master in High Performance Computing (MHPC) programme, recently published new research in the prestigious journal Letters together with ICTP researchers Marcello Dalmonte and Antonello Scardicchio (https://doi.org/10.1103/ PhysRevLett.120.030601). The article is titled “Many-Body Localization Dynamics from Gauge Invariance”.

Postgraduate Diploma Programme alumnus William Ugalde has been elected as head of the School of Mathematics at the University of Costa Rica.

Malik Maaza, from Algeria and a regular ICTP Associate, has been awarded the prestigious African Union Kwame Nkrumah Award for Scientific Excellence (AUKNASE) 2017, a major recognition at a Postgraduate Diploma Programme continental level for his pioneering alumnus Mostafa Hamouda has work in science and technology published a paper in the journal Climate and for his contribution in science Dynamics (https://doi.org/10.1007/ for African development. Professor s00382-018-4169-4). The paper, titled Maaza has pioneered and “Ekman pumping mechanism driving implemented numerous continental precipitation anomalies in response and national initiatives, including to equatorial heating”, was based the Nanosciences African Network on research he pursued with ICTP (NANOAFNET) launched jointly with climatologist Fred Kucharski. ICTP and TWAS.

16 Alumni News

Former ICTP postdocs Anton Mellit Ayesha Asloob Qureshi, a former from Ukraine and Erik Carlsson from the postdoctoral fellow in ICTP’s United States have published an article Mathematics section, is one of the first titled “A proof of the shufe conjecture” recipients of the Abdus Salam Medal (DOI: https://doi.org/10.1090/jams/893) (ASM) of the National Mathematical in one of the most prestigious journals Society of Pakistan (NMSP). Qureshi, in mathematics, the Journal of the who was at ICTP from 2013 to 2014, American Mathematical Society (JAMS). is currently an assistant professor at Sabanci University, Turkey, working in the area of commutative algebra. Qureshi was cited by the selection committee for “her remarkable papers published in good journals with a high impact on combinatorial commutative algebra. The concepts and ideas introduced by Qureshi continue to give rise to new and interesting developments in our field.”

Stanislas Ouaro, professor of mathematics and a former ICTP Junior Associate from 2003 to 2010, has been appointed Ministre de l’Education Nationale et de l’Alphabétisation of his country, Burkina Faso, earlier this year. Jehan Akbar, an ICTP Junior Professor Ouaro obtained his PhD Associate and former TRIL fellow, at Université de Ouagadougou in has been awarded substantial 2001. He has visited ICTP since 1999 research funding by the Pakistani as a participant in training activities, government for a project on both in mathematics and in climate “Analysis and characterization of modeling. He also spent research advanced materials, chemical and periods with ICTP’s Mathematics biological samples using optical section in 2005, 2006 and 2009 and and photothermal spectroscopy”. has collaborated with ICTP frequently The project includes the since then. In 2012, he was appointed establishment of the first optical president of Université Ouaga II, in (photothermal) spectroscopy Gonse, Burkina Faso. laboratory in Pakistan.

17 In Memoriam

GianCarlo Ghirardi Stephen Hawking Professor Ghirardi was associated with ICTP for The March passing of Stephen Hawking was many years as a researcher, a professor, and as keenly felt at ICTP, where many of his theories the head of its Associateships and Federation are studied. Director Fernando Quevedo Scheme. He attended the first-ever international is a colleague of Hawking at Cambridge’s seminar in theoretical physics in Trieste that was Department of Applied Mathematics and organized by ICTP co-founders Paolo Budinich Theoretical Physics as a professor of and Abdus Salam in the early 1960s and had theoretical physics there. “Knowing, seeing been a steady presence at the centre ever since. and interacting with Stephen have been some Ghirardi is well known for his contributions to the of the most extraordinary experiences in my foundations of quantum mechanics, as well as life. He was an exceptional human being, and I for his research, teaching and eforts to promote feel so fortunate to have had the opportunity to and develop physics. He was one of three meet him,” said Quevedo. authors of the so-called GRW theory.

George Sudarshan Theoretical physicist E. C. George Sudarshan Joseph Polchinski, a prominent theoretical was the recipient, together with Nicola Cabibbo, physicist and longtime friend of ICTP, was a of ICTP’s 2010 Dirac Medal, for fundamental professor at the Kavli Institute for Theoretical contributions to the understanding of weak Physics at the University of California, Santa interactions and other aspects of theoretical Barbara. His great contributions to theoretical physics. He discovered (with Robert Marshak) the physics, including the discovery of D- V-A theory of weak interactions, which opened –– a type of membrane in theory –– have the way to the full description of the unified led to advances in the understanding of string electroweak theory. The V-A theory was crucial theory and . In 2008, he shared to the work on the unification of the weak and ICTP’s Dirac Medal with Juan Maldacena and electromagnetic interactions by , for their fundamental contributions Abdus Salam and Sheldon Glashow, for which the to . three received the 1979 Nobel Prize in Physics.

18 Credits

Editor Mary Ann Williams

Scientific Editor/ Direttore responsabile Sandro Scandolo

Statistician Giuliana Gamboz

Writers Kelsey Calhoun Anna Lombardi

Photos Roberto Barnabà ICTP Photo Archives GianCarlo Ghirardi photo: Marino Sterle Joseph Polchinski photo: Massimo Silvano

Design Jordan Chatwin

Printed by Art Group Graphics s.r.l.

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