May 2007 Volume 16, No. 5

www.aps.org/publications/apsnews APS NEWS Highlights Climate Change is All About Energy A Publication of the American Physical Society • www.aps.org/publications/apsnews on page 8

Franklin’s Secret Message Revealed Reliving the Good Old Days of Superconductivity Twenty years after the Wood- and Alex Muller, at IBM Zurich, Cu-O compound. Initially they had stock of Physics session at the 1987 made their discovery of a lantha- seen only hints of superconductiv- APS March Meeting in which re- num-based cuprate perovskite that ity, and colleagues were skeptical searchers presented results on re- superconducts at 35K. that this unlikely ceramic compound cently discovered high temperature At the 2007 March Meeting, would superconduct. By October superconductors, many of the sci- Bednorz recounted how he and 1986, however, they had found the entists involved returned to speak Muller had worked for months on optimum composition and had ob- at the 2007 March Meeting. They the project before making the dis- served that the material exhibited reminisced about that exciting time covery. They were working with the Meissner effect, considered de- and commented on progress since copper oxides, rather than conven- finitive proof that the compound then. tional metallic alloys, and had tried was superconducting, and they sent This year also marks the 50th an- material after material with no suc- their paper off for publication. They niversary of the BCS theory of su- cess. It was frustrating at times, but won the Nobel Prize in 1987. perconductivity. Speakers at a spe- they kept going, Bednorz said dur- What made the discovery so ex- Photo by Ken Cole All the classes that had correctly deciphered Ben Franklin’s secret message cial evening session at the March ing the 2007 press conference. “We citing, said Bednorz, was that super- were entered in the drawing for the PhysicsQuest grand prize (see story Meeting spoke about the history and didn’t know whether it would be conductivity had been known about below). APS Executive Officer Judy Franz (left) picked the winner out of the impact of that theory. successful.” So he and Muller kept and studied for decades, since Ka- drum as Head of Public Outreach Jessica Clark looked on. The events leading up to the the work low key, working after merlingh Onnes first discovered the “French help arriving soon mystery centered on Benjamin Woodstock of Physics conference hours, using colleagues’ equipment. phenomenon in 1911. “The excite- in America.” That was the cor- Franklin, in celebration of the began in 1986 when Georg Bednorz Finally, they hit upon a La-Ba- SUPERCONDUCTIVITY cont. on 3 rectly decoded (fictional) mes- 300th anniversary of his birth. sage from Ben Franklin that The kit included materials and Physicists Present Latest Results in Graphene Maya Lampic’s sixth grade class instructions for four experiments and Metamaterials Research found when they had completed inspired by Franklin’s work with APS’s PhysicsQuest 2006 learn- lenses, electricity, and heat ab- Cutting‑edge research on new condition, the material’s electric a process in which a thin flat panel ing adventure. Their correct an- sorption. Each experiment gave materials is a major focus of the permittivity must be negative, and of the metamaterial would be able to swer, and a little luck, won them students a clue they needed to annual APS March Meeting, and in some cases, also its magnetic per- image an object at a spatial resolu- the grand prize: an iPod shuffle decode the secret message. the 2007 conference in Denver was meability. tion better than the wavelength of for each student, as well as some However, a typo in the man- no exception. Among the more in- Metamaterials made their debut the illuminating light. Ever since other prizes for the class. ual caused some classes to come teresting highlights was a series of at the APS March meeting in 2000. metamaterials were first realized The 20 sixth grade girls from up with the message, “American papers reporting new results in the At the time, only a couple of re- in the laboratory, physicists have Chicago were among thousands delicacies I now miss especial- areas of metamaterials–also known search groups were working in this been pushing the boundary of these of middle school students who ly.” APS accepted either answer as “left‑handed materials”–and gra- area; today there are dozens inves- “left‑handed” materials to shorter have decoded the message as as correct. phene. tigating ways to exploit the unique and shorter wavelengths. part of PhysicsQuest, APS’s Last fall, 8700 kits were sent Metamaterials are amalgams properties of these materials to pro- Shalaev and his colleagues have mystery-based science kit for to 2120 teachers (teachers could of tiny rods, strips and rings that duce perfect lensing and other odd reported a negative‑index material middle school students. Those register more than one class). exhibit a negative index of refrac- optical properties. operating at a wavelength of 770 classes that submitted the correct Kits are free to teachers who re- tion, thanks to their unusual, na- At the APS meeting in Denver, nm, the shortest yet observed for a answers were entered in a ran- quest them. By the March 2 dead- noscale‑engineered architecture, Purdue University’s Vladimir Sha- single‑negative material (exhibiting dom drawing to win prizes. line, 900 classes had submitted which enhances the magnetic in- laev reported on a new record‑set- only negative permittivity). Using The 2006 PhysicsQuest PHYSICSQUEST cont. on page 7 teraction between light and matter. ting metamaterial that might be the same material with a different To bring about a negative‑index ideal for so‑called “superlensing”: GRAPHENE cont. on page 6 Session Explores New Sources of Oil and Gas Heavy oils and natural gas hy- 1983, can be found on the sea floor March Prize and Award Recipients drates, which exist in vast reserves, near the coasts and underneath the could potentially become a sig- arctic tundra. Earth contains vastly nificant source of energy, but these more natural gas in hydrates than in resources are much more difficult conventional natural gas, said Collett and expensive to produce than con- in a press conference at the March ventional sources of oil and natural Meeting. “Hydrates are a very large, gas. At a March Meeting session on known source of natural gas,” he the future of fossil fuels and a related said. There has been increasing in- press conference, speakers provided ternational interest in recovering and assessments of these potential alter- using these resources, he said. native sources of oil and natural gas. Several missions have recently Natural gas consumption has explored some of these deposits and been rising rapidly, and is expected to estimated how much natural gas hy- increase 70% by 2025, said Timothy drate they contain. Estimates range Collett of USGS. The United States from 100,000 to 300,000,000 trillion currently consumes about 25 trillion cubic feet of natural gas hydrates on cubic feet of natural gas per year. Earth, compared with 13,000 trillion An alternative could be found in cubic feet of conventional natural gas hydrates, reported Collett. Hy- gas. The US has about 320,000 tril- drates are ice-like solids, in which lion cubic feet of gas hydrates, but water molecules trap the methane only 1200 trillion cubic feet of con- molecules in a cage-like structure. ventional natural gas reserves. Hydrates look a lot like ordinary ice, More research is underway to but they burn when lit with a match. assess more accurately how much Like conventional natural gas, hydrate natural gas exists and how most gas hydrates are methane- much of it might be recoverable, Photo by Cronin Photography based, and thus produce relatively Collett said. Front row (l to r): Franz Himpsel, Gabor Somorjai, Mark Kryder, Joel Miller, Arthur Epstein, John King, Edwin L. Gold- clean burning fuel. Burning methane Recovering the gas is challenging, wasser. Middle row (l to r): Uri Haber-Schaim, Chengkun Huang, William Wootters, Daniel Frenkel, Brooks Harris, Allan adds less carbon dioxide to the atmo- but possible. Several research proj- MacDonald, Samuel Bader, Kent Irwin. Back row (l to r): Hugh Churchill, Huanqian Loh, James Eisenstein, Timothy sphere than burning coal or oil. ects have shown that gas hydrates Zwier, Irfan Siddiqi, F. Bary Malik, Steven Girvin, Darrin Pochan, Glenn Fredrickson. Hydrates, first discovered in OIL & GAS continued on page 6  • May 2007 APS NEWS

Members in the Media This Month in Physics History

“Islands are special. They’re iso- security measures rely on the fact May 1932: Chadwick reports lated from urban predators, and that that computers are not fast enough includes people.’’ to decode information, The Globe the discovery of the neutron Ralph Nobles, on an island in and Mail, April 3, 2007 San Francisco Bay that he thinks “The glass bulb would be red-hot y 1920, physicists knew that most of the mass highly penetrating radiation emitted by the beryl- should be protected, San Francisco in the flame, and then they’d take the Chronicle, March 15, 2007 Bof the atom was located in a nucleus at its cen- lium consisted of high energy photons. Chadwick tube out of their mouth for a moment ter, and that this central core contained protons. In had noticed some odd features of this radiation, and “It seems a little unfair to the peo- and the thing would go, ‘woooo,’ It May 1932 James Chadwick announced that the core began to think it might instead consist of neutral ple whose last names begin with ‘W,’ would just sing to them.” also contained a new uncharged particle, which he particles such as those Rutherford had proposed. doesn’t it?” Greg Swift, Los Alamos National called the neutron. One experiment in particular caught his atten- Stanley Whitcomb, Caltech, on Lab, on an observation by 19th cen- Chadwick was born in1891 in Manchester, Eng- tion: Frédéric and Irène Joliot-Curie had studied the listing the authors alphabetically tury glassblowers, Associated Press, land. He was a shy child from a working class fam- then-unidentified radiation from beryllium as it hit on a paper by a large collaboration, April 2, 2007 ily, but his talents caught his teachers’ attention, and a paraffin wax target. They found that this radiation Wall Street Journal, March 16, 2007 “When you pay for your chil- he was sent to study physics at the University of knocked loose protons from hydrogen atoms in that “There’s a tremendous amount dren, you send them to school; you Manchester, where he worked with Ernest Ruther- target, and those protons recoiled with very high ve- of work building the apparatus, get- pay a lot of money for them. You ford on various radioactivity studies. locity. ting the experiment to work. But never expect that tomorrow they will In 1914, Chadwick decided to travel to Germany Joliot-Curie believed the radiation hitting the par- sitting there late at night in the lab, pay you back and you will get some to study with Hans Geiger. Unfortunately, not long affin target must be high energy gamma photons, but and knowing light is going at bicycle return. I think the attitude of the gen- after he arrived, WWI broke out Chadwick thought that explana- speed, and that nobody in the his- eral public to physics should be like and Chadwick ended up spend- tion didn’t fit. Photons, having tory of mankind has ever been here the attitude of parents to children. We ing the next four years in a prison no mass, wouldn’t knock loose before–that is mind-boggling. It’s do it for the future.” camp there. This did not entire- particles as heavy as protons worth everything.” Yuri Kamyshkov, University of ly stop his scientific studies. To from the target, he reasoned. Lene Hau, Harvard University, Tennessee, on why the public should Boston Globe, March 17, 2007 fund physics, Black Hills Pioneer, keep from being bored, he and In 1932, he tried similar ex- March 23, 2007 some fellow prisoners formed periments himself, and became “We’re not a charity. We’re not a a science club, lectured to each convinced that the radiation poor small struggling school in the “The Iditarod bug didn’t bite me. other, and managed to convince ejected by the beryllium was in South that’s going to fail if you don’t It swallowed me whole.” the guards to let them set up a fact a neutral particle about the give it money. I also make the case Eric Rogers, on running the small lab. Though many chemi- mass of a proton. He also tried that not all black men are in danger Iditarod, Anchorage Daily News, cals were hard to get hold of, other targets in addition to the of falling off a cliff.” March 17, 2007 Chadwick even found a type of paraffin wax, including helium, Walter Massey, Morehouse Col- “We took a pratfall on the world radioactive toothpaste that was nitrogen, and lithium, which lege, on raising money for the col- stage. What the analysis shows so lege, The New York Times, March far is that something extraordinarily on the market in Germany at the helped him determine that the 28, 2007 simple was missed in the design: the time, and managed to persuade mass of the new particle was the guards to supply him with just slightly more than the mass “That is based on the assump- obvious imbalance of axial forces AIP Emilio Segre Visual Archives that can occur.” it. Using some tin foil and wood of the proton. tion that nobody can crack it in time. James Chadwick Pier Oddone, Fermilab, on the he built an electroscope and did Chadwick also noted that There is no proof of it. You can only some simple experiments. because the neutrons had no hope [it doesn’t happen].” failure of a magnet built at Fermilab After the war, Chadwick returned to England, charge, they penetrated much further into a target Wolfgang Tittel, University of for the LHC, Associated Press, April where he finished his PhD in Cambridge in 1921 than protons would. Calgary, explaining that current data 3, 2007 with Rutherford, who was then Director of Cam- In February 1932, after experimenting for only bridge University’s Cavendish laboratory. Chad- about two weeks, Chadwick published a paper titled The Ethiopian Connection wick was able to continue to work on radioactivity, “The Possible Existence of a Neutron,” in which now with more sophisticated apparatus than tin foil he proposed that the evidence favored the neutron and toothpaste. In 1923, Chadwick was appointed rather than the gamma ray photons as the correct assistant director of Cavendish Laboratory. interpretation of the mysterious radiation. Then a Rutherford had discovered the atomic nucle- few months later, in May 1932, Chadwick submit- us in 1911, and had observed the proton in 1919. ted the more definite paper titled “The Existence of However, it seemed there must be something in the a Neutron.” nucleus in addition to protons. For instance, helium By 1934 it had been established that the newly was known to have an atomic number of 2 but a discovered neutron was in fact a new fundamental mass number of 4. Some scientists thought there particle, not a proton and an electron bound together were additional protons in the nucleus, along with as Rutherford had originally suggested. an equal number of electrons to cancel out the ad- The discovery of neutron quickly changed scien- ditional charge. In 1920, Rutherford proposed that tists’ view of the atom, and Chadwick was awarded an electron and a proton could actually combine to the Nobel Prize in 1935 for the discovery. Scientists form a new, neutral particle, but there was no real soon realized that the newly discovered neutron, as evidence for this, and the proposed neutral particle an uncharged but fairly massive particle, could be would be difficult to detect. used to probe other nuclei. It didn’t take long for Chadwick went on to work on other projects, but scientists to find that hitting uranium with neutrons kept thinking about the problem. Around 1930, sev- resulted in the fission of the uranium nucleus and Photo by Jessica Clark In March, the founding president of the Ethiopian Physical Society, Mulugeta eral researchers, including German physicist Walter the release of incredible amounts of energy, mak- Bekele of Addis Ababa University, visited APS headquarters as part of a US Bothe and his student Becker had begun bombard- ing possible nuclear weapons. Chadwick, whose visit. He is shown here at the American Center for Physics with Amy Flatten, ing beryllium with alpha particles from a polonium discovery of the neutron had paved the way for the APS Director of International Affairs. He discussed with her details of the APS program that enables Ethiopian institutions (as well as others in Africa) to re- source and studying the radiation emitted by the atomic bomb, worked on the Manhattan Project dur- ceive free online access to APS journals, a valuable resource because of the beryllium as a result. Some scientists thought this ing WWII. He died in 1974. good broadband access that these institutions possess.

Series II, Vol. 16, No.5 For Nonmembers–Circulation and Fulfillment Division, Editor-in-Chief (Plasma), Scott Milner (Polymer Physics), Paul Wolf May 2007 American Institute of Physics, Suite 1NO1, 2 Huntington Gene Sprouse*, Stony Brook University (on leave) (Ohio Section) APS NEWS © 2007 The American Physical Society Quadrangle, Melville, NY 11747-4502. Allow at least Past-President 6 weeks advance notice. For address changes, please John J. Hopfield*, Princeton University ADVISORS send both the old and new addresses, and, if possible, General Councillors Representatives from Other Societies Coden: ANWSEN ISSN: 1058-8132 include a mailing label from a recent issue. Requests Robert Austin, Christina Back, Elizabeth Beise, Wendell Fred Dylla, AIP; Harvey Leff, AAPT from subscribers for missing issues will be honored Hill, Evelyn Hu*, Ann Orel*, Arthur Ramirez, Richart Editor ...... Alan Chodos without charge only if received within 6 months of the Slusher*, International Advisors Associate Editor ...... Jennifer Ouellette issue’s actual date of publication. Periodical Postage Paid International Councillor Francisco Ramos Gómez, Mexican Physical Society Staff Writer...... Ernie Tretkoff at College Park, MD and at additional mailing offices. Albrecht Wagner Melanie Campbell, Canadian Association of Physicists Art Director and Special Publications Manager...... Kerry G. Johnson Postmaster: Send address changes to APS News, Mem- Chair, Nominating Committee Design and Production...... Nancy Bennett-Karasik bership Department, American Physical Society, One Margaret Murnane Staff Representatives Forefronts Editor...... Craig Davis Physics Ellipse, College Park, MD 20740-3844. Chair, Panel on Public Affairs Alan Chodos, Associate Executive Officer; Amy Flatten Proofreader...... Edward Lee Robert Eisenstein Director of International Affairs; Ted Hodapp, Director APS News (ISSN: 1058-8132) is published 11X yearly, ed to: Editor, APS News, One Physics Ellipse, College APS COUNCIL 2006 Division, Forum and Section Councillors of Education and Outreach; Michael Lubell, Director, monthly, except the August/September issue, by the Park, MD 20740-3844, E-mail: [email protected]. President Charles Dermer (Astrophysics), P. Julienne (Atomic, Public Affairs; Stanley Brown, Editorial Director; Chris- American Physical Society, One Physics Ellipse, Col- Leo P. Kadanoff*, University of Chicago Molecular & Optical Physics) Robert Eisenberg (Bio- tine Giaccone, Director, Journal Operations; Michael lege Park, MD 20740-3844, (301) 209-3200. It con- Subscriptions: APS News is an on-membership publi- President-Elect logical), Charles S. Parmenter (Chemical), Richard M. Stephens, Controller and Assistant Treasurer tains news of the Society and of its Divisions,Topical cation delivered by Periodical Mail. Members residing Arthur Bienenstock*, Stanford University Martin (Computational), Moses H. Chan (Condensed Groups, Sections and Forums; advance information on abroad may receive airfreight delivery for a fee of $15. Vice-President Matter Physics), James Brasseur (Fluid Dynamics), Peter Administrator for Governing Committees meetings of the Society; and reports to the Society by its Nonmembers: Subscription rates are available at http:// Cherry Murray*, Lawrence Livermore National Labora- Zimmerman* (Forum on Education), Roger Stuewer Ken Cole committees and task forces, as well as opinions. librarians.aps.org/institutional.html. tory (Forum on History of Physics), Patricia Mooney* Executive Officer (Forum on Industrial and Applied Physics), David Ernst Letters to the editor are welcomed from the member- Subscription orders, renewals and address changes Judy R. Franz*, University of Alabama, Huntsville (Forum on International Physics), Philip “Bo” Ham- * Members of the APS Executive Board ship. Letters must be signed and should include an ad- should be addressed as follows: For APS Members– (on leave) mer* (Forum on Physics and Society), Steven Rolston dress and daytime telephone number. The APS reserves Membership Department, American Physical Society, Treasurer (Laser Science), Leonard Feldman* (Materials), Akif the right to select and to edit for length or clarity. All One Physics Ellipse, College Park, MD 20740-3844, Joseph Serene*, Georgetown University (emeritus) Balantekin (Nuclear), John Jaros* (Particles & Fields), correspondence regarding APS News should be direct- [email protected]. Ronald Ruth (Physics of Beams), David Hammer APS NEWS May 2007 • 

Columnar Jointing Gives Rise to Natural Wonders Nose Out of Joint The famed Giant’s Causeway in into an almost hexagonal arrange- hooded monks–she observed while northern Ireland is justly considered ment. This network carves out the viewing glaciers in the Andes. to be one of the seven wonders of columns.” Along with colleagues at the the United Kingdom. Local legend Similar structures can be created Ecole Normale Superieure in holds that the causeway is the rem- with a simple kitchen experiment: France, Betterton created the first nant of a bridge spanning the chan- mix equal parts corn starch and wa- artificial versions of these spiky nel between Ireland and Scotland, ter and place into a coffee cup. Dry ice formations, which can be found built by an Irish giant named Fionn the mixture by shining a bright light quite frequently on high-altitude mac Cumhaill (Finn McCool). above it. Within a week or so, the glaciers where the air is particularly The causeway consists of nearly mixture will be completely dry and dry. She also devised a mathemati- 40,000 interlocking basalt columns, you can break it apart to reveal an cal model to predict the process. some as tall as 36 feet. The tops of interior that is broken up into “starch The hope is that this research will the columns from “stepping stones” columns.” yield useful insights into how gla- leading from the foot of the cliffs In addition to studying the genu- ciers evaporate; it may also lead to a before disappearing under the sea. ine article in situ in both Ireland and practical strategy for preserving gla- It looks far too regular in terms of Scotland, Goehring and his cohorts ciers in light of global warming. Photo by James Riordon Tim Gay’s nose is out of joint because, as shown in the picture, he tried, and its patterned structure to have been have figured out how to control this Penitentes arise when the sun’s failed, to balance a gyroscope on the tip of it. Gay, professor of physics at the caused by natural processes–yet it tabletop kitchen experiment so pre- rays evaporate snow in such a way University of Nebraska, was giving a public lecture at the APS March meeting was. cisely that they can study the forma- that the ice turns directly into water on “the physics of football”; he has written a book with the same title, and is celebrated for his video spots shown at halftime on the stadium jumbotron A fellow of Trinity College tion process in much greater detail vapor, without melting into water during Nebraska football games. The gyroscope on his nose was meant to named Sir Richard Bulkeley II of- than scientists could in the past, first. The process is called subli- demonstrate conservation of angular momentum, but even though it fell off, ficially announced the causeway’s augmented by X-ray tomography to mation. The snowy surface might the audience of several hundred, which included many school-age children, enjoyed the lecture and seemed to appreciate how much physics there is in existence in 1693, in a presentation give the first genuinely 3D imaging start out smooth, but it gradually blocking, tackling, punting and passing. before the Royal Society of Lon- of the internal structure of the col- develops depressions as some areas SUPERCONDUCTIVITY continued from page 1 don. Theories abounded as to how umns. sublimate faster than others, and the ment is that even in an established high temperature superconductivity, the causeway had formed. In 1771, Among the more surprising find- resulting curved surfaces concen- field, revolution is still possible,” he and many of the expected applica- a Frenchman identified only as De- ings: (1) the columns are not quite trate more sunlight and speed up said. tions have not appeared, speakers marest announced that it was the re- as perfectly hexagonal as previous- the sublimation even more, leaving The initial high Tc discovery was pointed out. At the time nothing sult of volcanic activity. ly believed, and (2) the continuous behind a forest of towering spikes confirmed by a Japanese group and According to physicist Lucas of ice. Penitentes are nature’s ice seemed impossible; more great de- then by Paul Chu of the University Goehring of the University of sculptures. velopments were expected to be just of Houston. Chu discovered Y-Ba- Toronto–who presented a paper Rising temperatures slow the around the corner. But while engi- Cu-O, the first compound to super- at the 2007 APS March Meeting formation of penitentes quite a neers have made a number of minor conduct above liquid nitrogen tem- in Denver describing his recent bit, an especially alarming fac- improvements in high Tc materials, perature. While working towards work in this area with fellow tor in light of global warming, there have been no major break- the discovery, he went many nights Toronto colleague Stephen Mor- because fewer ice spikes could through in the past 20 years. No with only three hours of sleep, and ris–the columnar joints that make accelerate the melting of gla- one has made a room temperature only saw his family at Christmas, up the causeway were formed ciers. The spikes cast shadows, superconductor, and it is not known Chu recalled at this year’s meeting. roughly 60 million years ago by and serve as a natural cooling whether such a material is possible. By March 1987, dozens of re- the cooling and shrinking of mol- mechanism. There’s a working There are some applications for search groups were working on ten lava from a massive volcanic hypothesis that spreading a small the high Tc materials, but no com- The Giant’s Causeway similar high T compounds. About eruption. layer of dirt over glaciers could help c pany is making a profit on high 50 physicists spoke at the marathon When the lava flowed into the dynamics of the formations can be preserve them by fostering faster temperature superconductivity, said “Woodstock of physics” session sea, it quickly cooled, contracted, found even deep inside the struc- formation of penitentes. Grant. Chu predicted that high Tc held at the APS meeting in New and crystallized into the near-perfect ture, similar to dry foams. Also, the This turned out to be true with wires might actually first be used by York that year. Two thousand physi- hexagonal columns we see today. (In size of the columns depends on the the small-scale versions Betterton developing countries that don’t al- cists packed the room and over- fact, geologists believe there were speed at which the cracks advance, created in her lab. She spread printer ready have a power infrastructure. flowed into the hallway until after 3 three major lava flows, giving rise and the rate at which the water can toner on her artificial snow layer to Moreover, there is still no accept- am, when the session finally ended. to lower, middle and upper basaltic move through the starch. That’s simulate pollutants common to gla- ed theory that explains high tem- The public was excited too, ex- layers, with the causeway columns why lava-formed columns are 1000 ciers around the world, and found perature superconductivity, making pecting this development would occurring in the middle layer.) That times larger than the tabletop ex- that the ice spikes grew more rap- it an important unsolved problem, lead to amazing applications such kind of shrinkage inevitably causes periment: the analogous properties idly as a result. It’s a bit counter-in- speakers said. “It rivals the unifica- as extremely efficient power trans- stresses that fracture the rock. of lava are much slower. tuitive, since carbon-based pollut- tion of the forces,” Grant said. mission and superfast levitating “The columns are formed as a Sharing the session with Goeh- ants actually increase melting rates Although there is no explanation trains. Paul Grant, who was at IBM sharp front of cooling moves into ring was Meredith Betterton of the on glaciers because the ice absorbs for high temperature superconduc- Almaden in 1987, said in the 2007 the lava flow, assisted by the boil- University of Colorado, Boulder, more sunlight and therefore heats press conference that even high tivity, conventional low tempera- ing of groundwater,” said Goehring. who became enthralled by the large up more quickly. The formation of school students got in on the high ture superconductors are explained “As the front advances, it leaves be- icy spikes–called penitentes because more penitentes could offset that T excitement by producing one of by the BCS theory, which celebrates hind a crack network which evolves they resemble a procession of white- damage. c these relatively simple compounds its 50th anniversary this year. A spe- in their own school lab. Grant also cial evening session at the March Quantum Leap Reported for Entangled Photons remembered how physicists were Meeting commemorated that anni- General purpose quantum com- quantum key, a string of bits used relay quantum communications be- treated like rock stars for that short versary. puters may still be a long way in the to decode a message in a quantum tween two locations on Earth. period of time. For instance, bounc- In 1957, John Bardeen, Leon future, but a number of advances in cryptography scheme. A quantum In addition to sending quantum ers at trendy New York nightclubs Cooper, and Robert Schrieffer de- quantum computing and quantum encrypted message would be essen- codes over longer distances, Zeil- brought physicists to the front of the veloped the first complete micro- information were presented at the tially unbreakable, since any attempt inger is planning to set up a real line. All they had to do was show an scopic theory of superconductivity. March Meeting. at eavesdropping would destroy the quantum cryptography network in APS meeting badge. In the theory, electrons form “Coo- For instance, Anton Zeilinger of message, making the eavesdroppers Vienna. Five participating groups Speakers at the 2007 March per pairs” that move in a coordinat- the University of Vienna has trans- presence known. would each build the hardware for Meeting also discussed progress ed manner. At the March Meeting, mitted a quantum key wirelessly In a press conference, Zeilinger their own nodes, and they would since 1987. Since then, more than Doug Scalapino of the University of over a distance of 144 km, between likened the entangled photons to a then be able to send each other 100 high Tc materials have been dis- California, Santa Barbara, said the two of the Canary Islands. This is pair of “quantum dice,” that would quantum encrypted messages across covered. Y-Ba-Cu-O is still best for BCS theory was a major milestone. the longest distance quantum infor- always show the same number no the city. Zeilinger hopes to launch many applications, Chu said. Under “It was a remarkably complete de- mation has been transported through matter how far they are separated. the network in 2008. pressure, Y-Ba-Cu-O still holds the scription.” He said. “I think they the air. Earlier this year the group re- Quantum cryptography systems record for highest Tc, at 164K. changed the way we think about Zeilinger reported the record- ported having transmitted a quan- are commercially available, Zeil- Many questions remain about condensed matter physics.” breaking feat at the March Meeting. tum key using pulses containing inger pointed out, but as far as he He and his research group produced more than one photon. At the March knows they have only been used for Wineland and other researchers Pan of the University of Heidel- entangled photons on the island La Meeting, they reported for the first research, not for encrypting data. have been working to reduce the berg and Hefei National Laboratory Palma, then sent one of the photons time the transmission of single pho- Several groups reported at the size of these traps, because smaller in China, described his 6-photon through the air to a receiving tele- tons, which are more secure. March Meeting on progress towards traps would enable faster comput- quantum computer. He said his goal scope on Tenerife, 144 km away. The rate of data transmission quantum computers. ers, Wineland said. However, the is to have a ten-photon quantum The European Space Agency op- through the air was slow, at just 178 David Wineland of NIST leads ions tend to overheat in small traps. computer in five years. erates telescopes on those islands, photons in 75 seconds. one of several groups working on Wineland’s design, with all elec- Researchers generally agreed located off the coast of Africa. The Zeilinger says this experiment ion trap quantum computing, cur- trodes on a single layer, resembles a that a practical quantum computer telescopes were ideal for the appli- demonstrates the possibility of send- rently one of the most advanced computer chip. It could potentially is a distant goal. “It’s far too early cation because they are sensitive ing messages over much longer dis- quantum computation technologies. reduce the overheating problem and to say what a future quantum com- enough to detect single photons. tances. He is now proposing a more In these systems, ions are trapped serve as a building block for a larger puter will look like,” commented The photons’ polarization states, ambitious scheme of using satellites with electric fields, and then manip- quantum computer. Zeilinger during the press confer- representing 0s and 1s, form a or the International Space Station to ulated with lasers to act as qubits. Also at the meeting, Jian-Wei ence.  • May 2007 APS NEWS Letters Correcting the Record on Pauli Nepal Protest Brings At APS, the Embargo I read with interest the “This first edition of the Handbuch der Dirac’s important contribution Results Has Already Gone Month in Physics History” column Physik (1925). 3) The first clear (conmutators from Poisson brack- Regarding the picture with the “The Back Page” article in in the January APS News on Wolf- attribution to the spin, as an internal ets) is of November, 1925, and headline “Getting high on phys- the March APS News last month gang Pauli and the exclusion prin- angular momentum responsible of even Erwin Schrödinger’s wave ics”, published in the March 2007 entitled “The Embargo Should ciple. Although the article is essen- the electron’s fourth quantum num- mechanics is of January, 1926. Not APS News, I would like to inform Go” urged that scientific journals tially correct, fair and accurate, I ber is by the US physicist Ralph two years later. you that the number of students not put embargoes on publicity have a few little objections to it. In Kronig, who in January, 1925 was 5) Among the many things due in the physics class at Tribhuvan relating to their articles. There particular: in Tübingen, Germany when Pauli to Pauli you omit, the most impor- University in Nepal has increased. has not been any embargo of 1) In January, 1925, as stated, was visiting. Actually, Pauli, in tant one is that, with Heisenberg, This happened because of the dem- news stories published in Physi- Pauli formulated the exclusion his usual sarcastic way, rejected he was responsible for the formula- onstration by students on Decem- cal Review and Physical Review principle, BUT it was of course Kronig’s idea right away, saying it tion of Quantum Theory of Fields, ber 12, 2006 in front of Nepal’s Letters for over 22 years. See in the frame of the Old Quantum was a “good joke” (the full story, in two papers in 1929 and 1930. Ministry of Education and Sport, the Editorial by an earlier Edi- Theory. narrated by Kronig, is in “Sources 6) It is true that he devoted a lot as shown in the picture, in which tor-in-Chief [D. Lazarus, Phys. Hence, the first statement is of Quantum Mechanics” edited of time and energy to philosophi- they demanded greater access to Rev. Lett. 52, 2101 (1984)]. So NOT forbidding fermions to be in by van der Warden). In fact, Kro- cal and other issues, but that was physics classes. APS members can be assured the same quantum STATE. What nig was a bit angry with the later throughout his whole life, not only that our journals anticipated, Pauli said is this: There cannot be Uhlenbeck-Goudsmit hypothesis, at the end, and until the very end, Tirtha Raj Joshi and followed, the advice in the two electrons with the same four as he had advanced it before. he was concerned with fundamen- Akron, OH “Back Page” quite a while ago. quantum numbers. 4) It is not true that “... In the tal physical problems: in 1955 he 2) I am not aware of Pauli being two years after Pauli’s ...exclusion produced a fundamental paper on Editor’s note: The author, a Gene Sprouse disconcerted with the Old Quan- principle, the new quantum me- the CPT theorem, and even replied master’s student in physics at the APS Editor-in-Chief tum Theory of Sommerfeld. On the chanics took off...” by letter, in early 1957, to the news University of Akron, is from Nepal. contrary, he for example encour- Here’s the record: Heisenberg’s of parity violation. aged Heisenberg to work on it. Lat- decisive Quantum (Matrix) Me- er he wrote a masterly exposition chanics was ready in June, 1925, Luis J. Boya of the Old Quantum Theory for the and appeared during that summer. Zaragoza, Spain Not Every Experiment Has to be Done Mehrdad Adibzadeh (Let- out.” While I agree that this is interpretation of quantum me- ters, March APS News) writes, disturbing, allow me to point chanics, thought experiments “What is disturbing... is the out that this statement applies that can be found in many clas- claim that an almost-effortless not only to claims of humble sic textbooks on quantum me- experiment would have a cer- versus arrogant scientists, but chanics. Twelve-Year Term Limits Twelve Years Later tain outcome to support a cer- also to so many of the thought By Michael S. Lubell, APS Di- And get on with a life that really tain point of view, when it ap- experiments of the early 20th N. Sukumar rector of Public Affairs counts. parently has never been carried century on the foundations and Troy, NY A dozen years ago, flush with “But wait, there’s more!” as Claims for Wind Power Greatly Overblown their victory in the 1994 congres- the late Arthur Schiff, king of sional elections, the brash new Re- the infomercial, used to say as he The letter by Mike Jacobs [APS tion (20-25%) of the installed power turbines. publican leadership brought H.J. was slicing and dicing his way to News, March 2007], which touts capacity. Production and usage of elec- Res. 73 to the floor of the House riches peddling his Ginsu knife on wind energy as a viable contribu- Germany is half the size of Texas trical energy must be completely of Representatives. The resolution late-night TV. Term limits mini- tion to solving our energy problems, but has more than twice the installed matched at all times; any mismatch would have amended the United mize the creation of political fief- contains several mistakes and omis- wind power capacity of the entire can lead to blackouts. In the case of States Constitution by imposing doms and the entrenched policies sions that are not apparent in a non- US, namely 20,424 MW (in 2006). the German system this can lead to 12-year term limits on members that go along with them, provid- technical discussion. To judge what Nevertheless, the large investment blackouts covering large parts of Eu- of Congress. Senators would have ing, in the process, the opportunity wind energy can actually contribute, in wind energy (16,394 MW in rope; it has come so close a couple been able to serve a maximum of for the constant churning that lets one has to work with realistic num- 2004), produced only 4.9% of Ger- of times that the Dutch and Polish two full terms, and Representa- new ideas bubble up with regular- bers. many’s electricity usage. The prob- grids were also threatened. tives would have had to clean out ity. Sounds so good, I’m almost I illustrate this with the example lems created by large investments in Jacobs’ statement that Den- their offices after six terms. ready to buy into it. of the 150-MW wind park planned wind power are discussed honestly mark manages to generate 20% of The House passed the bill by a But just as I never bought a in the Gulf of Mexico opposite (a rarity) in the Wind Report 2005 its electricity from wind “without 227 to 204 vote, with 189 Republi- Ginsu knife, I’m not quite ready to Galveston, Texas (at a cost of $300 of E.ON Netz (Ref. 1), Germany’s storage and back-up capacity” is cans and 38 Democrats supporting strike the bargain. My experiences million). This park will deliver, at second largest electrical utility. One completely wrong; Norway and it and 40 Republicans, 163 Demo- on the Hill the last four months best, at the rate of 30 MW. Com- conclusion of the report is that the Sweden perform these functions crats and 1 Independent opposing will tell you why. paring with the actual energy use possibility of wind replacing con- for Denmark. Excess Danish wind it. But the initiative failed to gar- First scroll back to 2005. That of Texas, this will provide electrical ventional energy sources is quite energy is shipped to these coun- ner the two-thirds majority needed January, amid much Washington power for less than one extra minute limited. Germany’s wind-energy tries where it relieves the load on for a Constitutional amendment, hoopla, the Council on Competi- per day for Texas. Moreover, if one system in 2004 could only contrib- the hydroelectric reservoirs; in turn and it died formally, at least on the tiveness released its annual com- wants to keep up with a 1.5% annual ute 8% of its output capacity (1312 electricity shortages in Denmark federal level. Still, in the frothy petitiveness report, raising ques- increase in electrical usage in Texas MW) to secure production of the get replenished by these countries. atmosphere of the 1994 “Newto- tions about the nation’s future eco- by installing only wind power facili- system. So an extra conventional Without these arrangements Den- nian” revolution, many members nomic status on the global stage. ties, one would have to build about generating capacity of about 90% of mark would be subject to many of Congress took a pledge to retire A month later, the Task Force on 25 of these wind parks every year! the installed wind capacity had to be crippling black-outs. Finally, Ja- within twelve years, and amaz- the Future of American Innova- The reasons that in an actual available as backup. This requires cobs’ assertion that not a single MW ingly some of them remained true tion issued its first R&D Bench- comparison with conventional pow- an enormous additional investment. of back-up capacity for wind energy to their principles. Count Repub- marks Report, containing trend er generation, wind energy performs The report also stated that the lican Bill Frist of Tennessee, who lines that painted a grim picture of has been required in the US is prob- so dismally are the following: 1. Air feed-in of wind energy can change last year was Majority Leader of future U.S. competitiveness in the ably due to the fact that the US wind is a very dilute medium that moves often and quite dramatically. On the Senate, among them. high-tech arena. energy system consists of so many at low speeds. 2. The energy that can Christmas Eve 2004, wind produc- It’s been twelve years since By early spring, key Senators widely dispersed (relatively) small be extracted from the wind varies as tion in Germany fell 4000 MW in former House Speaker Newt and Representatives had become systems, so that the local base-load the 3rd power of the wind speed; so, 10 hours, representing the capacity Gingrich asked his colleagues to so alarmed that they asked the generators can still take care of any for example, if the wind speed drops of eight 500 MW coal fired power take the twelve-year pledge, and National Academies to set up a by one half, the energy drops by a plants! This created an enormous fluctuations. This will change in the it’s time to ask the question, do study panel and quickly recom- factor of eight. As a result, wind tur- challenge for the operators of the future when a substantial fraction of term limits make sense? Do the mend policy changes to address bines don’t produce any energy for grid and it could easily have led to the base load (e.g. 20%) is supposed good public servants who took the the issue. The panel, chaired by low wind speeds, i.e. below Beau- a vast blackout in central Europe. to come from wind energy. pledge and followed through on Norman Augustine, retired CEO fort 4 (a ‘moderate breeze’,12-18 About 7000 wind turbines spread The E.ON Report should be re- their commitment deserve kudos? of Lockheed-Martin, completed mph, the prevailing wind in most out over Germany (from the North quired reading for all those people For being honest, reliable and its work in less than six months, cases). 3. Over a period of days Sea to the Swiss border) were feed- who think and say, “The more wind principled, without a doubt! But and their report, “Rising Above the wind can be extremely variable ing into the grid, but Fig. 3 of Ref. energy the better.” beyond that, have they really done the Gathering Storm,” was on the so that energy is not produced in a 1, which displays the wind energy Reference a good deed? desks of Members of Congress steady stream but in a succession of feed-in for the entire year, clearly 1. E.ON Netz Wind Report 2005 If you think that the best gov- and their staff by the end of Oc- spikes between zero and full power, shows frequent variations between (in English) available at www.eon- ernment is the least government, tober. which can create a serious challenge 0.2% and 38% of the daily peak netz.com/EONNETZ_eng.jsp you’d probably say yes. Put in a A month later, House Demo- for the grid operators. The combined grid load. This contradicts what Ja- few years of public service, get crats issued their “Innovation result of these facts is that the wind cobs asserts about a leveling effect Frits de Wette out and return to the real world, Agenda” and the Senate began to turbines deliver only a modest frac- of geographically dispersed wind Austin. Texas where markets dictate outcomes. BELTWAY continued on page 5 APS NEWS May 2007 •  Smart Organisms Use Physics To Find Their Food Oklahoma High School Physics Student The humble single-celled of finding food. ral noise” in the water fleas. Wins Intel Science Talent Search amoeba lacks access to a handy More complex, higher organ- Scientists have known for Zagat’s guide when it comes to isms, like zooplankton, have many years that biological sys- Mary Masterman, a commercial systems. foraging for its food. But ac- also evolved a highly efficient tems frequently rely on stochas- 17‑year‑old student from Okla- Using a laser as her light cording to Liang Li of Princeton hunting strategy. Ricardo Gar- tic resonance as a stimulus to homa City, beat out a field of 40 source, Masterman tested sev- University, amoebae don’t need cia, with the Center for Neurody- the sensory systems, which in finalists and won the top award eral household objects and sol- one. They have a built-in mecha- namics at the University of Mis- turn can affect the behavior of of the 2007 Intel Science Tal- vents–including acetone and tol- nism for an optimal food-forag- souri in St. Louis, talked about creatures both great and small– ent Search in March. She will uene–and compared her results ing strategy. his research on the role of spe- usually in positive, optimizing receive a $100,000 scholarship to published wave numbers. Li presented a paper on the cific swimming characteristics ways that improve the creatures’ from the Intel Foundation for Even with her inexpensive laser topic at the 2007 APS March in achieving optimal food forag- chances or survival. The neural building an accurate homemade light source, she found she could Meeting in Denver. For instance, ing strategies for zooplankton. noise of water fleas influences Raman spectra system out of a make relatively accurate wave- scientists previously assumed The work is the first observation the turning angle in such a way laser, a digital camera, a variety length measurements with her that microbes move in random in a living animal of an inher- as to enable the creature to ex- of lenses, and a prism‑like object homemade device. She hopes patterns unless they are specif- plore the most amount of space to disperse light. to attend MIT or Caltech after ically hot on the scent of tasty and gather the most food within A senior at Westmoore High graduation. nibbles. Yet Li has found that a given time frame. School, Masterman built her For a complete list of this species of amoeba called Dic- The observed noise inten- spectrograph system at home for year’s winners, see http://www. tyostelium seem to remember sities correlate with the width $300, compared to the $20,000 to intel.com/education. its previous “steps” and use of distribution of the turn- $100,000 price tag for high‑end that remembered information ing angles favored by the wa- to explore new ground, there- ter fleas, and it turns out that BELTWAY continued from page 4 by increasing their chances of the creatures gather the most finding food. Photo by W. van Egmond amount of food in a single for- draft bipartisan innovation leg- high-level staff; the ins would be- How can such a simple organ- Daphnia aging session at a very specific islation. In short order the White come the outs. For the Republican ism have any kind of memory at ent swimming characteristic–the noise intensity. “A small noise House unveiled the American Party as a whole, voters ironically all? Li thinks there may be a clue turning angle–that optimizes the intensity means that the animal Competitiveness Initiative (ACI) had enforced the twelve-year term in the mechanism by which the food obtained in a patch of fixed obtains less than the maximum that contained a blueprint for dou- limit. creature moves: namely, by rear- size for an organism foraging for possible amount of food within bling the aggregate budgets of the Periodic change is certainly ranging its body into protruding a fixed time. its patch during its fixed feed- Department of Energy’s Office good for government, but with shapes known as pseudopods. Garcia and his colleague, ing time,” said Garcia. “Like- of Science, the National Science change often comes a loss of in- Using phase contrast mi- Frank Moss, studied the zoo- wise, less food is ingested if the Foundation and the core programs stitutional memory. Visit a con- croscopy, Li tracked a teeming plankton Daphnia, more com- distribution is too broad.” The of the National Institute of Stan- gressional office today and men- sample of Dictyostelium over monly known as water fleas. findings were consistent across dards and Technology. So im- tion the “Gathering Storm” report 100 hours, charting the “runs” They looked at the swimming all five species of Daphnia stud- printed had the competitiveness or ACI, and more often than not, and “turns” they made, which movements of five different ied, regardless of size or age of issue become, that by the sum- staffers will give you a vacant formed a zigzag pattern of mo- Daphnia species of varying the organisms. mer of 2006, you couldn’t find a stare. Talk to any one of the 54 tion. She specifically looked at sizes, all of which exhibit a Garcia suspects that this nat- House or Senate member or, for new Representatives and 10 new how often the creatures made a distinct hop-pause-turn-hop se- ural stochastic resonance may that matter, any legislative direc- Senators about innovation and left turn followed by a right turn, quence while swimming. They have a played a significant role tor in a congressional office, who and found they showed a clear analyzed the turning angles the in the evolution of sensory sys- hadn’t heard about the “Gathering competitiveness, and you will find bias for that kind of variation. creatures made after each hop in tems, although he is careful to Storm” report or the ACI. consternation. Li reported that the formation the sequence, plotting the num- emphasize that his results don’t But by midnight on November Six months ago, I was mulling of pseudopods leaves temporary ber of times a given angle was outright prove this hypothesis; 6, everyone on Capitol Hill knew over what issue I would person- “scars” in the cell’s cytoskel- observed on a histogram. they merely offer strong sup- that the congressional world was ally turn to next, with the matter eton, and this makes it far more These turning angles were al- porting evidence in favor of that about to be set spinning.With the of science research and education likely that the next pseudopod most, but not quite, completely notion. In the case of Daphnia, Democratic victory at the polls, and their connection to global the creature forms will point random–they found evidence of Garcia believes that the water the pecking order was about to competitiveness fairly well under- in a new direction. Because it a preferred turning angle value, flea’s distinctive swimming pat- change: the minority would be- stood by the Hill. Term limits have changes direction and doesn’t based on a mathematical analysis terns evolved over tens to hun- come the majority; minor play- changed all that. They may not be retrace its steps, it covers more of the underlying random pro- dreds of millions of years via ers would become major players; good for consistency in policy, but ground and increases its chances cesses, or intensity of the “neu- Darwinian natural selection. low-level staff would become they keep lobbyists employed. Physics Models Brought to Bear on Gene Transfer, Viral Vaccines Something that continues to among other research. At the evolved to store genetic informa- end up suppressing the creation chooses a winning set of T-cells, puzzle scientists about the fossil APS March Meeting in Denver, tion in a modular form, and to of new antibodies when the body it has a natural tendency to go record is that single-celled life Deem reported that he has now accept useful modules of genetic is exposed to a new strain of the with those cells when it’s con- forms first appeared about 3.5 developed “the first exact solu- information from other species,” flu. fronted by new strains of the billion years ago, with another tion of a mathematical model of said Deem. The phenomenon has also same disease in the future,” said 2.5 billion years passing before evolution that accounts for this Deem’s prior work on flu vac- been observed in dengue fever Deem. “For HIV, we found a di- multi-celled organisms finally cross-species genetic exchange.” cines–notably, the use of nuclear and HIV. The latter was the top- rect correlation between the level made their debut on the scene. He attributes the phenomenon to spin glass modeling to better pre- ic of a second paper by Deem’s of competition among T-cells However, it took just 1 billion horizontal gene transfer (HGT), dict which strain of the flu virus research group presented at the and the rate at which the virus years for every other conceivable in which the DNA from one Denver meeting. HIV is an es- escaped.” form of life to evolve: plants, species is introduced into an- pecially difficult virus to eradi- Deem has devised a potential mammals, birds, insects, reptiles other. cate, in part because it mutates new strategy for a more effective and any other terrestrial species. Deem found that by ac- so quickly after initial infec- HIV vaccine. He thinks that inoc- That’s a significant increase in counting for HGT–in addition tion, producing several differ- ulating someone at various points the rate of evolutionary develop- to point mutations and sexual ent virus strains. It’s an inge- on the body against different ment. The standard cited mecha- recombination–his model can nious “divide and conquer” strains simultaneously could all nisms for evolution are point demonstrate how HGT in- strategy, according to Deem: but eliminate competition among mutations–“random changes in creases the rate of evolution by the human immune system T-cells, so that the HIV will be single nucleotides on the DNA spreading favorable mutations responds to viral infection by trapped in a permanently latent chain, or genome”–and recom- across populations. producing antibodies to ward state, never raging out of control bination, which occurs when the So it is possible to swap off any given strain, but it tends to develop into full-blown AIDS. genetic sequences of a set of par- entire sets of genetic code, in- to only focus on a single strain; There are lymph nodes scat- ents are recombined (“sexual se- cluding the genes that allow the rest just run rampant. tered throughout the body, re- lection”). But models that simply bacteria to develop resistance T-cell competition takes sponsible for producing those take into account these two com- to antibiotics–and for the hu- HIV virus infecting a cell two forms, per Deem’s com- all-important T-cells, but it takes mon mechanisms really don’t man immune system to continu- was likely to dominate in any puter models: original antigenic four or five days before any T- explain the sudden rapid accel- ally adapt to invasive species, given year–exploited the phe- sin (also known as “deceptive cells produced therein leave the eration of evolutionary rates in- an attribute Deem has traced to nomenon of “original antigenic imprinting”), and immunodomi- node and spread throughout the dicated by the fossil record. an HGT insertion that occurred sin.” The antibodies produced nance, which occurs when sev- body. Simultaneous inoculation Enter Rice University physi- some 400 million years ago. In by the body’s immune system to eral viral strains simultaneously would mean that each different cist-turned-bioengineer Michael fact, he thinks that a significant fight exposure to the flu virus be- infect a single person. The cells node would select for a differ- Deem, who has a penchant for portion of our DNA was donated come part of the body’s “memo- that respond to each strain com- ent strain, with no single T-cell adapting mathematical models by viruses and bacteria that in- ry” so that it can fight off future pete until one emerges the vic- emerging as dominant, because from physics to the mutation fected our ancestors over lots and exposure to the same flu strain. tor. immunodominance doesn’t have and evolution of the flu virus, lots of generations. “Life clearly However, those same antibodies “Once the immune system time to kick in.  • May 2007 APS NEWS

Burn, Baby, Burn Microbe-Based Sensors Can Improve Security Physicists are finding new ways ria can integrate themselves into the nalnd, is working on developing to improve security with astronomi- silica film, and can even direct the terahertz radiation detectors that cally inspired scanners and microbe- formation of the tiny structures that could be used for security scanners based sensors. serve as protective houses for the in airports or other places. The scan- Jeffrey Brinker of the University microbes. Brinker calls the develop- ner, based on instruments long used of New Mexico and Sandia National ment a “new approach to engineer- in astronomy, would detect terahertz Labs reported at the March Meeting ing with life.” radiation people naturally emit. a way to make microbe-based sen- The structures protect the cells, It measures radiation using an sors that could be used for security and the lipids provide nutrients and array of superconducting microbo- applications. The project originally keep the cells from drying out. The lometers, niobium wires that heat started when DARPA wanted to de- cells stay alive for weeks to months, up when they absorb radiation emit- velop “insect reconnaissance.” They even in harsh environments where ted by the subject. Most clothing approached Brinker, asking him to they would not normally survive, materials are transparent up to about develop tiny biocompatible sensors such as in a vacuum or under an 1 THz, so a good THz detector that could be attached to the backs electron microscope. could see through clothing to spot of bees or other insects. Many of the tiny cells can be concealed weapons. These sen- Photo by Ed Lee The insect reconnaissance proj- printed onto a surface to make ar- sors could detect concealed weap- ect never worked out, but the re- rays of sensors on tiny chips, he No, they’re not trying to set the paper on fire with a magnifying glass. Adrian ons up to 100 meters away, so the Carmichael and Jeff Osborne, two participants in the APS Teachers’ Day at search did lead Brinker to develop said. technology could be used to scan the March meeting, are performing a perfectly safe optics experiment. Sev- a way to build tiny biocompatible The cells can be engineered to enty-seven teachers from the Denver area attended the day of workshops, nanostructures. Living calls can fluoresce in the presence of toxic people without their knowledge, talks, and networking. integrate themselves into those chemicals, explosives or pathogens. said Helisto. structures, which nurture and pro- They can be used to detect just The scanners would not have GRAPHENE continued from page 1 tect them. The living cells can be about anything, Brinker said. They high enough resolution to reveal light polarization, they achieved a made on the experimental front. engineered to glow in the presence could test water or air for chemical anatomical details, making the tech- wavelength of 815 nm, the shortest In Denver, Pablo Jarillo‑Herrero of chemicals or pathogens, and thus or biological weapons. They could nology appealing to both the pub- yet observed for a double‑negative of Columbia University gave an can be used as sensors for security also be used to study disease, for lic and the authorities. Images are material (exhibiting both negative overview of the latest experimental applications. instance as a platform to study the similar to those created by infrared permittivity and permeability). developments in this rapidly grow- Brinker make these structures by onset of dormant diseases like tu- sensors, said Helisto. Unlike x-ray An even hotter research topic ing field. For instance, researchers mixing up a solution of lipids and berculosis, suggested Brinker. scanners, the sensors don’t subject these days is graphene, essentially have successfully developed gra- silica and living cells. As the solu- In another security-related de- the person being scanned to any ra- one‑atom‑thin carbon sheets. Physi- phene ribbons. Among the more tion dries into an ordered solid film, velopment, Panu Helisto, of VTT diation, and so do not present any cists are also excited about the very interesting recent findings is that the living cells such as yeast and bacte- Technical Research Center of Fi- health issues, said Helisto. unusual behavior of electrons mov- resistivity of the material changes ing through a graphene landscape: according to the width of the rib- namely, you can increase the elec- bons, which means that the semi- Martian Features Provoke Sharp Debate trons’ energy without increasing conducting properties of graphene Geological features on Mars, than flowing water. He created a Though the patterns in the lab their velocity, almost as if the elec- could be tailored to suit the applica- including some strange sharp fea- simple setup to find out. He placed experiment are on a much smaller trons were behaving like slow‑mov- tion. tures called razorbacks, have been a pile of light, hollow glass beads scale than those on Mars, Shinbrot ing light waves. Jarillo‑Herrero also summarized suggested as evidence of liquid in a box and tilted it. As the box is believes they are comparable be- At last year’s March Meeting other recent progress in the field, water. However, granular materials cause the grains settle slowly com- in Baltimore, there were presenta- including the observation of super- researcher Troy Shinbrot of Rutgers pared with the speed at which they tions on graphene by only a few conducting graphene transistors by University has found that these fea- flow downhill, as dust grains would groups. This year, there were doz- researchers at Delft University in the tures could be produced by dry dust in Mars’ low gravity. ens. Graphene‑related research Netherlands; freely suspended gra- grains rather than flowing water. He Sharp features resembling the has exploded, thanks in part to its phene sheets, a room‑temperature reported his results at the March razorbacks seen on Mars could adaptable mechanical and electrical Hall effect, and room‑temperature Meeting. also be produced in a similar setup properties, with some 180 research single‑electron transistors with gra- The pointy razorbacks, a few in the lab by applying an electric papers published on the topic in the phene–the latter by a research group centimeters high and less than a field to the grains, Shinbrot found. past year, mostly on the theoretical at the University of Manchester in centimeter wide, photographed When the box was tilted, some of aspects, but progress has also been England. by NASA’s Mars rovers, have in- Photo courtesy of NASA/JPL/Cornell the tiny grains clumped together as trigued observers. Some scientists Razorbacks photographed by they became airborne, and landed believe they may have been pro- NASA’s Mars rover Opportunity in the spiky formations similar to Advanced Lab Instructors duced recently by flowing water. tipped, the light grains create a mini Martian razorbacks. Electric fields Other stream-like features on Mars dust storm and eventually settle could build up on Martian sand Plan New Organization have also been cited as evidence of down. Shinbrot found that he could grains as they slide past each other A new association for advanced helpful, said Reichert. Members of water. make the glass grains fall in patterns because Mars is so dry, he reported. undergraduate physics laboratory in- the association could advise each Shinbrot wondered whether resembling many features seen on “These features that look like water struction is being formed. At an ini- other on improving these courses, these features could be associated Mars, from wide apron-like features may simply be dry features,” said tial session held at the 2007 March selecting and using appropriate with completely dry grains rather to thin sinuous streams. Shinbrot. Meeting, participants shared plans equipment, and convincing depart- and ideas for the organization. ments to purchase equipment, said Wolfgang Christian of Davidson OIL & GAS continued from page 1 The purpose of the new associa- Reichert. College is one physicist who plans can be produced by either heating and use. “The real problems are ac- tion will be to foster communication The new association will give to join the organization. “I have the hydrates or decreasing the pres- cessing it and being able to produce among advanced lab instructors and TeachSpin an opportunity to mar- been teaching advanced laboratory sure to release the gas. More testing enough,” said Schmitt. to provide some professional recog- ket its products, Reichert says, but off and on for 25 years and I think it of these methods is still needed, said Heavy oil can be extracted using a nition for them. members of the association will important to share experiences and Collett. process called steam assisted gravity “The group is trying to put the benefit as well. to pass on knowledge to new fac- Environmental concerns associ- drainage. This involves drilling two focus of the physics community At the March Meeting, about 35 ulty,” he said. ated with hydrate production include horizontal bore holes and injecting back on advanced lab,” said Jona- people attended a reception for ad- Another potential member is possible damage to the sea floor or steam into one of them. The steam than Reichert, who is playing a vanced laboratory instructors spon- David Pullen of the University of possible accidental release of meth- heats the heavy oil, making it flow leading role in starting the organi- sored by TeachSpin and the APS Massachusetts, Lowell. He also ane gas. Any project that produces more easily. The process works, said zation. Reichert is the president of Forum on Education. About 25 of looks forward to sharing ideas with gas hydrates would have to deal with Schmitt, but is costly. TeachSpin, a company that makes the attendees indicated they were members of the new organization. these concerns, said Collett. How- In order to make the process as instruments for physics laboratory interested in joining the new asso- There has been some attention ever, accidental release of methane is efficient as possible, Schmitt says it instruction. The new association ciation, at a cost of $10. TeachSpin paid to freshman labs, he said, but unlikely, he said. is important to improve our knowl- was initially the idea of Krishna will also contribute to the founding not so much focus on advanced Based on the limited studies done edge of the properties of the heavy Chowdary, now at Bucknell Uni- of the association. Recichert said he lab, and this organization can help so far, Collett believes hydrates could oil and the surrounding rock. He and versity, said Reichert. would like at least thirty people to change that. He hopes the new or- become economically competitive his group are using sensitive seismic Most universities do offer ad- sign up before the association is of- ganization will work with APS and with conventional natural gas. vanced labs for undergraduates, ficially launched. AAPT. Another promising source of en- imaging techniques to monitor the though there are some schools that The association might meet a Potential members are being ergy is heavy oil, Doug Schmitt of heavy oil production process. They don’t. couple times a year, Reichert pre- asked to vote on a name for the new the University of Alberta reported. have used these techniques to locate These courses can be difficult dicts. Lab instructors could bring organization; possibilities include: Significant heavy oil reserves exist in where the largest oil deposits are and time-consuming to teach, and their equipment and share ideas on Advanced Laboratory Physics As- Canada, South America, and Colo- within the rock. They have also been they require expensive equipment. implementing laboratory experi- sociation (ALPhA), Consortium rado, while most of the world’s light able to trace the steam as it is injected In some cases, physics depart- ences, he envisions. for Advanced Laboratory Instruc- oil reserves are in the Middle East. during the extraction process, poten- ments have very limited resources Once the organization is tion (CALI), and Advanced Physics Heavy oil looks like sand with tially making it possible to use the for these classes. People who teach launched, Reichert expects some of Laboratory Association (APLA). tar added, Schmitt said. Though steam more efficiently. Alternative these courses may feel isolated and the new members will take charge For more information, contact Jon- heavy oil is abundant, because it is technologies to extract the heavy oil unrecognized, so contact with other of leading the new organization and athan Reichert (jreichert@teach- so thick–its viscosity is similar to are also being investigated, Schmitt advanced lab instructors could be any committees it may form. spin.com) peanut butter–it is difficult to extract said. APS NEWS May 2007 • 

Biomolecules Ready For Their Close-up Then You Diagonalize the Hamiltonian... with New Imaging Methods Physicists are constantly devel- the cells madly multiply with wild Pennsylvania has employed the oping new and improved methods abandon. Laser light shines on both force sensing mode of standard to get better pictures of cancer cells the object and the CCD camera, atomic force microscopy to image and protein molecules that are so and the reflected light is fed into the molecules of fibrin, a protein that critical to human health. Two such system, which records very detailed acts as a molecular spring to keep methods were described by speak- information about depth and motion blood clots structurally stable, but ers at the APS March Meeting in of the components at work in the tu- still flexible enough to allow blood Denver. mor tissue. to flow through them. Cancer cells, for instance, shim- All that outer shell activity shows Fibrin develops in the blood mer impressively for CCD cameras up as a bright shimmer in the result- from another protein called fibrino- when imaged with a new technique ing image, while the dead tissue at gen, when blood cells release the called digital holographic imaging. the center doesn’t move at all (What enzyme thrombin in response to en- It produces time-lapsed, dynamic little shimmer there is at the center countering damaged tissue. speckled images that “shimmer” in can be attributed to the incidental Last year, researchers at Wake response to cellular motion. Recent motion of the CCD cameras record- Forest University, Harvard, and work at Purdue University marks ing the experiment). Using this tech- the University of North Carolina the first time holography has been nique, it’s possible to create handily used AFM to test the stretchiness Photo by Brian Mosley used to study the effects of a drug color-coded “motility maps” of cel- of fibrin, and found these fibers can Carlos Meriles (left), Assistant Professor of Physics at CCNY, chats with Brian on living tissue, according to David lular activity at three different tissue stretch much further before break- Baird (D-WA), Chairman of the Subcommittee on Research and Science Edu- Nolte, the Purdue University phys- depths: 120, 190, and 330 microns. ing than other biological fibers–in- cation of the House Science and Technology Committee. Meriles, who is the ics professor who headed up the Red indicates high activity, and is cluding collagen, spider silk, and recipient of an NSF Career Award, testified before the subcommittee on March research. found at 120 microns. By 330 mi- keratin. That property is crucial to 29 as it considered priorities for the NSF. More information on the NSF hear- ings can be found at http://www.aip.org/fyi/2007/038.html . Conventional microscopy tech- crons, that activity has slowed suf- fibrin’s ability to stop the flow of niques don’t delve very deeply into ficiently that the contrast color is blood, which exerts a great deal tissue. Nolte wanted to get a peek predominantly yellow. Completely of mechanical stress on the fibers. inside the tissue itself, preferably dead tissue shows up as blue. There have also been studies dem- M. Hildred Blewett Scholarship at a depth of about 1 millimeter, to So cellular motion becomes a onstrating that fibrinogen taken for Women Physicists gain a better understanding of its built-in contrast agent used to en- from patients with heart problems This scholarship has been established to enable women to structure. hance the image, making digital ho- forms stiffer clots than that taken return to physics research careers after having had to interrupt He has combined holographic lographic imaging a vital emerging from healthy control patients. those careers for family reasons. The scholarship consists of an imaging with laser ranging, which tool in measuring the effectiveness Brown saw an intriguing cor- award of up to $45,000. The applicant must currently be a legal measures how long it takes for a la- of anti-cancer drugs like colchicine. relation between heart disease and resident of the US or Canada. She must be currently in Canada or ser pulse to travel to an object and If the drug is working, there will be the mechanics of fibrin in blood the US and must have an affiliation with a research-active educa- be reflected back. “The holography a reduction in the motion of the or- clotting, and thought that protein tional institution or national lab. She must have completed work gives us the peaks and valleys and ganelles, which will show up with unfolding might play a role in the toward a PhD. detailed depth information, while less shimmer in the image on the unusual elasticity (“stretchiness”) • Applications are due June 1, 2007. Announcement of the the laser ranging allows us to con- computer display, and can then be of fibrin fibers. He used AFM in award is expected to be made by August 1, 2007. trol how deep we are looking,” he quantitatively analyzed. combination with total internal re- said. “We have moved beyond achiev- flection fluorescence microscopy • Details and online application can be found at http://www. Nolte’s new imaging technique ing a 3D image to using that image to measure the force with which aps.org/programs/women/scholarships/blewett/index.cfm measures the motion of organelles for a direct physiological measure of this unfolding occurs–marking the Contact: Sue Otwell in the APS office at [email protected] inside cancer cells to determine what the drug is doing inside cancer first time the mechanics of fibrino- whether they’re living or dead. Or- cells,” said Nolte. “This provides gen has been measured at the single ganelles play a key role in fostering valuable information about the ef- molecule level. Estate Planning Session the out-of-control cancer cell divi- fects of various doses of the drug He found that protein unfolding Held at March Meeting Call for sion that so often proves fatal to the and the time it takes each dose to does indeed seem to play a role in Nominations patient. become significantly affected.” the mechanics behind blood clot- An estate planning session His imaging system creates a Nolte’s isn’t the only research ting. Next on the agenda is to ex- was held at the March Meet- 2008 APS Excellence in hologram of a tumor whose center group finding innovative new ways plore whether this unfolding plays ing for meeting attendees and Education Award is usually filled with necrotic tissue to image biological molecules. any kind of role in clot mechanics at local APS members. John A. Deadline: July 1, 2007 surrounded by an outer shell where Andre Brown of the University of more modest extensions. Warnick, a partner in the Den- The award, which con- sists of $5000 and a cer- PHYSICSQUEST continued from page 1 ver office of Holme Roberts & Owen LLP, provided an tificate citing the achieve- answers, 290 of which were cor- to the connection between electric- PhysicsQuest first started in overview of estate and wealth ments of the recipients, was rect. Those that sent in the correct ity and magnetism. It was great,” 2005. “PhysicsQuest was initially transfer planning. Topics in- established to recognize answers were eligible for a random she said. developed as a way for middle cluded the importance of hav- and honor a team or group drawing to win prizes. All classes Both Lampic and her students school students to celebrate the ing a will, considerations when of individuals (such as a col- that submitted results received a are already looking forward to next World Year of Physics 2005, but placing principle assets in joint laboration), or exceptionally certificate of participation. year’s PhysicsQuest. “I have 5th has since grown into a much larger names, gift tax exclusion op- a single individual, who has The five first place classes - re graders coming up to me excited to project,” said Rand. portunities, the importance of exhibited a sustained com- mitment to excellence in ceived PhysicsQuest journals, a be able to be part of PhysicsQuest With PhysicsQuest 2006 com- record-keeping and maintain- physics education. gift card for science-related materi- next year.” she said. pleted, kits are being developed for ing an up-to-date estate plan, Five copies of the nomina- als supplies, and a skyrail suspen- Lampic is making good use of next year’s activity, which centers and tips on how to choose an tion packet should be submit- sion kit. Maya Lampic’s 6th grade the prizes–a colleague will use the on the young Marie Curie, who executor or trustee. ted to the chair of the selec- class, at Sacred Heart Schools in skyrail kit for a physics project, and grew up in Warsaw at a time when Handouts and brochures Chicago, won the grand prize: iPod the gift card will help her equip her distributed at the session are tion committee, Ken Krane, women were not allowed to attend at the following address: shuffles, a $500 gift card for sci- science room for next year. college there. Each of the experi- available free of charge to APS ence-related materials for the class, APS public outreach coordina- Department of Physics ments will give students a clue they members. Those who missed PhysicsQuest journals, and a sky- tor Kendra Rand said, “Teachers Weniger Hall 301 need to help Marie and her class- the session can get copies by rail suspension kit. love that PhysicsQuest kits are fun Oregon State University mates avoid being caught as they contacting Darlene Logan at Lampic and her classes partici- and motivating for their students [email protected] or (301) 209- Corvallis, OR 97331-6507 study in secret. The kit will include pated in PhysicsQuest in 2005, and and develop lab skills in line with 3224. Electronic submissions experiments on heat, energy, and again in 2006.“The students enjoy the standards teachers are required will not be accepted. The temperature. solving the problems to get clues to to teach. Most of them look for deadline for nominations is “Registration for the 2007 kit Correction: the final answer,” she said. “They the catch when we tell them the July 1, 2007. Further infor- has been open for less than two In the Spring Prizes and enjoy the different experiments, kits are free because they see the mation may be obtained on weeks and we already have requests Awards Insert in the March and I am introduced to some new value in the product. I wish that the APS website at http:// from over 700 teachers represent- APS News, we erroneously ones I have not earlier thought of. APS members could see the teach- referred to NIST as the Na- www.aps.org/programs/hon- To be introduced to famous sci- ers’ reactions when we explain that ing more than 3,000 classrooms tional Institute of Science and ors/awards/education.cfm entist and learn about less known the project is funded by the profes- of 6th-9th grade students,” said Technology. The correct des- or by contacting the chair sides of them is intriguing.” sional society for physicists. The Rand. “I think this is a testimony to ignation is the National Insti- of the selection committee She has even gotten some extra teachers are grateful for the free the need within the middle school tute of Standards and Tech- at [email protected] use out of her 2005 PhysicsQuest materials, but I think what touches education community for accurate, nology, reflecting its previous state.edu. kit. “After Benjamin’s Franklin’s them even more is that the physics fun physical science materials and incarnation as the National Bureau of Standards (NBS). secret message, I used materials community recognizes that what to the difference that support and We thank Frank J. Lovas for from Albert’s Einstein’s hidden they do in the classroom makes a encouragement from the physics pointing this out. treasure to introduce the students difference.” community can make.”  • May 2007 APS NEWS The Back Page

limate change is all about energy, a subject familiar to makers as well. California’s history of independent regu- Cany physicist. Climate changes are driven by changes lations, an ironic positive legacy of horrendous air quality in the Earth’s energy balance with space, either as the re- Climate Change in the Los Angeles basin, provides telling examples. Pri- sult of variations in the distribution or intensity of incom- marily through mandating more efficient use of energy, ing solar radiation reaching the Earth, the fraction of that California has held its per capita energy use roughly con- radiation that is reflected, or the emission of thermal radia- is All About Energy stant since the early 1970s (http://www.energy.ca.gov/ef- tion back to space. The greenhouse effect alters the latter, ficiency/). During that same period, per capita energy use By Drew Shindell trapping outgoing terrestrial radiation. A reduction in emis- has gone up ~50% nationwide. California’s advanced sions during recent decades at exactly the wavelengths efficiency standards started in the 1970s for major appli- where greenhouse gases (GHGs) absorb has been directly ances such as furnaces, air conditioners and refrigerators. measured from space, so there is no question about this They have been so successful that energy use by these effect. Thus the relevant question is how sensitive is the Earth’s appliances has dropped 25, 40 and 75%, respectively. In con- climate to changes in the planetary energy balance? trast, the federal government only imposed standards in the Climate records from the distant past show that the Earth’s early 1990s, when most of the efficiency gains had already climate is not immutable, but in fact is rather sensitive, especial- been realized. Standards have also been gradually increased ly at long timescales. Climate models are not given credence by for buildings and utilities to use and generate energy efficiently. the climate science community unless they exhibit sensitivity Contrary to the dire warnings sometimes heard from industry, consistent with paleoclimate evidence. Given a sensitive cli- the effect of standards has not been to destroy manufacturers by mate, the increasing greenhouse effect should be causing our driving up the price of their product. Today’s refrigerators that planet to warm up substantially. Modern measurements show use one-quarter the energy of their 1970s predecessors and also that indeed the Earth as a whole has unquestionably warmed cost roughly 60% less. Precedent shows that technology always since the industrial revolution. However, climate records don’t seems to keep up with the regulations. Though industrial groups indicate causality on their own. Instead, a combination of cli- are currently suing California over its recent attempt to regulate mate data and understanding of the many potential drivers of emissions from automobiles more strictly, it’s hard to accept energy changes is required to attribute cause and effect. Perhaps will almost certainly decrease, making the future prospects that current regulations are adequate. Can some of the country’s surprisingly, this is often easier to do in the distant past than in for warming even worse than one would estimate considering most talented scientists and engineers really not come up with more recent times, as the potential sources of energy balance GHGs alone. a way to make more fuel efficient cars than we did in the 1970s changes were far fewer prior to large-scale industrialization. Thus climate science tells us several key things. Our plan- (when current fuel efficiency standards were largely set)? With this in mind, we can explore the relative roles of natu- et is warming. The abundance of GHGs in the atmosphere is The benefits of having avoided the national increase of 50% ral factors and human contributions to the warming since the increasing due to human activities, and these are enhancing in per capita energy use are tremendous. California emits 18 industrial revolution. The strength of past solar variations is not the greenhouse effect. Natural forcings appear not to have in- million tons less carbon per year, has greatly reduced emissions well known (the timing is known, but not the amplitude), so creased during recent decades, and only minimally during re- of smog precursors and particulate, both harmful to human while the global mean warming of the early 20th century can be cent centuries. The Earth’s climate sensitivity is constrained health, and consumers save ~$12 billion in energy bills each at least partially reproduced in models by imposing increased well enough from studying the Earth’s history to know that year. This is money into the American economy instead of into solar output, this by itself tells us little. Climate variations over the enhanced greenhouse effect will lead to substantial warm- foreign economies that seem almost inevitably to use their oil the past several centuries provide a more useful constraint, and ing in the absence of offsetting effects, and future offsetting ef- and gas income to maintain authoritarian regimes and often also indicate that given what we know about climate sensitivity, so- fects (primarily from aerosols) are likely to decrease. So global to fund schools where fundamentalists are trained to hate the lar variations very likely were the dominant driver of long-term warming during the 20th century is very likely largely caused United States. Clearly using energy more efficiently is in Amer- (multi-decadal and longer) climate variations during the last by the GHG increases, and warming in the future is very likely ica’s best economic and national security interests in addition millennium. Models are able to match the hemispheric aver- to increase. Most estimates find a warming of 2-2.5 C to consti- to environmental ones. Energy, economic and environmental age temperature changes and large regional changes, such as tute “Dangerous Anthropogenic Interference” with the climate, success stories also exist in the developing world. For example, the 17th and 18th century cooling in Europe and parts of North a term meaning a high likelihood of severely disruptive or even Brazil’s sugarcane ethanol program for vehicles, begun in the America that gave rise to the name ‘Little Ice Age’, best when catastrophic climate changes which most of the world (includ- 1970s in an effort to stop spending roughly half its earnings we assume past variations in solar output were extremely small, ing the US) has pledged to avoid. The Earth has warmed ~0.8 C from exports on oil imports, has been enormously successful. only ~0.1-0.2%. Such small variations imply that solar forcing already, and another ~0.6 C will take place as the planet adjusts Following decades of work, ethanol now sells for less than tra- (here forcing means an “external” change affecting the climate to its current energy imbalance with space. Thus we have only ditional gasoline without any subsidies and has saved Brazil system’s energy balance) may have contributed to the warming another 0.6-1.1 C to go. It will be almost impossible to avoid over $50 billion in oil imports, far more than the program cost. of the early 20th century, but that it was too small to be the sole this much additional warming without prompt, large-scale ac- At the same time it has created domestic jobs and substantially driver. tion worldwide. reduced the country’s vulnerability to Middle Eastern oil crises. How about the more rapid warming of the last 40 years? What can we do? Again, it comes down mostly to energy. A Efforts to wean the US from imported oil have, in contrast, been Much of this time the sun has been monitored by satellites, and whopping 80% of today’s energy comes from fossil fuel burn- largely rhetorical. ing, releasing huge quantities of CO (the most important GHG there has been no substantial increase in its output. Tellingly, so- 2 Continued use of fossil fuels is inevitable for the immediate lar increases would heat the stratosphere more than the surface, forcing) into the atmosphere. While future projections of the future, and potential solutions such as carbon sequestration and and observations show instead that the stratosphere has been world’s population and economy are much less certain than nuclear power require further study or remain controversial. cooling rapidly. This cooling is partially due to ozone depletion, even climate projections, most plausible futures show a large There are no compelling reasons, however, that the US can- but is also present at altitudes where there has been little ozone increase in energy usage, with double to triple current usage in not rapidly become dramatically more energy efficient. Energy change, and stratospheric cooling is a well-known response 50-75 years. There are two clear options. First, energy can be efficiency is not just a win-win situation, it’s at least a “win to to GHG increases. Thus the spatial structure of atmospheric generated from renewable sources that do not generate GHGs. the fourth,” improving air quality and human health, reducing temperature change doesn’t fit the impact of solar increases. Second, energy can be used more efficiently. Given the scale of climate disruptions, improving national security and boosting Instead, it bears the signature of increased GHGs. However, the problem, it seems clear that both are imperative (along with the American economy. Similarly, capture of methane released GHGs trap so much energy that were they the only important efforts to halt and reverse deforestation, especially in the trop- to the atmosphere from landfills, pipelines, mining and other ics, which also contributes substantially to atmospheric CO factor the planet would be warming even more rapidly than ob- 2 sources reduces global warming and air pollution (methane served. It’s clear that the enhancement of the greenhouse effect increases). is a precursor to ozone, a component of smog) and provides is being partially offset by aerosols (particulates), though details Physics can contribute greatly to both strategies. Further im- a valuable economic commodity (natural gas) that makes the of these are poorly understood at present. Hence as for the early provement in renewable energy from wind, solar, and nuclear long-term economics positive. Factoring in the costs of adverse 20th century, the uncertainty in the forcing limits the value of power should be near or at the top of national priorities. Instead, health impacts of fine particles, reductions in black carbon soot comparing models with observations of global mean tempera- US energy research and development spending is today only also often lead to a net economic gain. Thus even without in- ture trends. One can put in increasing GHGs and then offset the 40% of what it was in 1980. A ban on construction of coal-fired cluding the economic cost of climate change via a carbon tax power plants that do not design in the capacity to add carbon right amount with aerosols to reproduce the late 20th century or cap-and-trade system for CO2, many global warming mitiga- global mean trend, but little is learned. A more convincing rea- sequestration in the future is required for a serious effort to limit tion strategies make economic sense already for ancillary rea- CO emissions. While there are substantial economic costs to son to trust the climate models is that when these are driven 2 sons. These are not put into practice due to systemic problems. with increasing GHGs and other forcings, they are capturing limiting coal burning and increasing use of renewable energy, at For example, soot emitters do not pay the health costs, so lack more and more of the regional response of temperature and least in the short-term, there are significant potential economic an incentive to control emissions. Builders do not pay the occu- precipitation seen in observations, including cooling in certain gains as well and the technology is ready. In the EU, the expan- pant’s energy bills, so are not motivated to strive for efficiency. regions and decreased rainfall in much of the subtropics. sion of wind energy since the 1990s has eliminated the need for Similarly, distributed power generation with use of waste heat Though aerosols have been offsetting a poorly quantified nearly 50 new coal-fired plants, and renewable energy there is saves energy, but utilities understandably aim to increase sales, but certainly substantial portion of GHG forcing, they are un- now a $20 billion industry. Physicists are also at the forefront of not reduce them. Leadership is required to overcome these sys- likely to continue doing so. For one, GHG forcing is growing developing more efficient ways to use electricity, such as solid- temic problems and benefit society as a whole. Much is con- ever larger, so to offset a constant fraction would require ever state lighting. Electricity generation is currently only ~37% tentious in the US regarding solutions to global warming, but larger aerosol emissions. Instead, aerosol emissions have been efficient, with nearly 2/3 lost in generation, transmission and increasing energy efficiency and other “win-win” strategies decreasing in the developed world as a result of air quality legis- distribution, leaving ample room for improvement. Distributed should not be. lation, and are projected to do so in the developing world during generation with capture and use of waste heat is a simple way to Drew Shindell is a senior climate scientist at NASA’s the next 10-40 years. So while poor understanding of aerosols more than double the efficiency of electricity generation. Goddard Institute for Space Studies in New York. He is also is sometimes cited as a reason to doubt warming projections, While science and engineering are crucial to solving our en- a lecturer in the Department of Earth and Environmental Sci- in fact the crucial point about aerosols is that their influence ergy and climate problems, there are important roles for policy ences at Columbia University.

APS News welcomes and encourages letters and submissions from its members responding to these and other issues. Responses may be sent to: [email protected]