February 2006 Volume 15, No.2 APS NEWS www.aps.org/apsnews A Publication of the American Physical Society Inside this issue

DOE Picks University of to Use the Sorting, sorting... Head Los Alamos Management Team New APS Logo he Department of Energy of exceptionally high caliber,” said announced in December its Energy Secretary Samuel Bodman Tdecision to award the contract at a press conference in December to manage Los Alamos National announcing the decision to award the Laboratory to Los Alamos National contract to the UC/Bechtel team. Security, LLC. (LANS), a partner- Bodman stressed that the new con- ship led by the University of tract would not be a continuation of California, partnered with Bechtel the previous contract. “This is a new Corporation, a huge engineering, con- contract, with a new team, marking struction and project management a new approach to management at Los Photo credit: Ernie Tretkoff company. Alamos.” The 2006 March Meeting received more than 6500 abstracts, and The University of California has That new approach includes a new sorting them all into sessions is a highly non-trivial task. Undaunted, For camera ready versions a dedicated group of volunteers, part of which is pictured here, gath- run Los Alamos National Lab since attitude towards monetary compen- of the logo visit the lab was created in 1943. But a sation. The new contract, which http://www.aps.org/logo.cfm ered at APS headquarters in College Park on December 9 and 10 for series of safety, security, and financial begins June 1, has an initial term of this purpose. As the picture shows, a great time was had by all. problems in the past two years cast seven years, with a provision to extend doubt on the university’s ability to it to 20 years. Under the new contract, manage the lab, and the DOE decid- the LANS team will receive up to De Gennes, Ben Lakhdar and Wagner to Deliver ed to put the contract out for a com- $79 million per year, depending on petitive bid. performance. Previously, the Endowed Lectures at March and April Meetings Some at Los Alamos believe the University of California had received problems have been blown out of about $9 million per year to manage This year two named APS lec- was nominated for the Beller of the 2005 UNESCO–L’Oréal proportion, and the contract didn’t the lab. tureships will bring distinguished Lectureship by the Division of prize for Women in Sciences for need to be rebid. Other major labs The new contract “begins a new foreign scientists to speak at the Polymer Physics. her experiments and models on have similar levels of safety and secu- era for Los Alamos,” University of March and April meetings. The The 2006 Marshak lecturer infrared spectroscopy and its rity, said Brad Holian, a Los Alamos California President Robert Dynes speakers were selected by the will be Zohra Ben Lakhdar of the applications to pollution, detec- physicist. “It’s not that Los Alamos said in a statement after the APS Committee on International University of Tunis. She will give tion and medicine. Ben Lakhdar is singularly bad. It seems to me is it announcement. “I believe this was Scientific Affairs (CISA), from a talk at the March Meeting enti- was nominated for the Marshak was a drive to privatize. I think it’s a an excellent decision and one that is nominations submitted by various tled “Scientists in Developing lectureship by the Forum on very bad idea.” right for both Los Alamos and the APS units. Countries: Is there an effective International Physics. The LANS partnership that will country.” The Beller Lectureship was way to support meaningful At the April Meeting, the take over the management of the Details on how operations at the endowed by Esther Hoffman research?” Ben Lakhdar’s Beller Lecture will be given by lab includes the University of lab will change under the new man- Beller for the purpose of bring- research focuses on atomic spec- Albrecht Wagner, director of California, Bechtel Corporation, agement have not been announced. ing distinguished physicists from troscopy, and she is devoting her DESY, the German particle BWX Technologies, and “This new contract will put in abroad as invited speakers at APS career to carrying out applied physics laboratory. Wagner has Group International. They were com- place concrete measures of account- meetings. The lectureship pro- research to meet national needs been a leading proponent of the peting for the contract against a team ability, ensuring that the tax dollars vides support for speakers at the in . She is the recipient Endowed Lectures continued on page 11 led by Lockheed Martin and the spent at Los Alamos are well spent,” March and April meetings. University of . said Bodman. The Marshak Lectureship, Symposium Caps WYP “Both proposals were strong and UC continued on page 11 endowed by Ruth Marshak in honor of her late husband and Talent Search Program former APS president, Robert APS Commemorates Compton Marshak, provides travel support As a closing event for the World Ambassadors from the United for physicists from a developing Year of Physics, students from States, and also for those from country or Eastern Europe invit- about 20 different countries attend- , Cameroon, Ghana, ed to speak at APS meetings. ed a special “Physics Young Indonesia, and Tanzania, to the sym- The March Beller lecture will Ambassadors” symposium in posium in Taipei. The American be given by Pierre-Gilles de Taipei from December 31, 2005 to Association of Physics Teachers Gennes, of the Collège de . January 4, 2006. These students, helped coordinate travel for these De Gennes is a leading exponent ages 10-18, were chosen to attend groups. of soft condensed matter physics. the event through an international At the international symposium, He received the 1991 Nobel Prize program, the WYP 2005 Talent students attended a wide variety of in Physics for his generalization Search. events, including presentations by of physical order descriptors to The International Coordinating distinguished physicists, a “physics complex soft matter. At the March Committee for the Talent Search is fun”session with hands-on activ- Meeting, de Gennes will present was chaired by Beverly Hartline ities, a poster session for the stu- a talk on “The Nature of Memory of Heritage University. The NSF dents to present their work, a Objects in the Brain.” De Gennes provided travel grants for the Young Taiwan Symposium continued on page 3

Photo credit: Mary Butkus On December 12, then APS President-elect (now APS President) Optical Illusion presented a plaque in honor of Arthur H. Compton at For most of 2005, a giant banner Washington University in St. Louis. This was the third plaque to be pre- with the World Year of Physics logo sented as part of the ongoing APS historic sites initiative; the first two hung down the side of the building hous- honored Benjamin Franklin in Philadelphia, and Michelson and Morley ing the Optical Society of America in at Case Western Reserve University in Cleveland. Compton was a pro- Washington, DC. It became a familiar fessor at Washington University, studying the scattering of X-rays, when sight to commuters as they exited the he discovered the effect named after him in 1922. As part of the presen- Dupont Circle Metro station. But nothing tation ceremony, Hopfield signed the APS Ledger of Historic Sites. lasts forever, and as the World Year of Watching as he signs the Ledger are John Rigden (center), Chairman, Physics faded into memory (see Viewpoint APS Historic Sites Committee, and Mark S. Wrighton, Chancellor, on page 4) so too did the OSA banner. Washington University in St. Louis. Photo credit: Gary Stoiber 2 February 2006 APS NEWS

This Month in Physics History February 1968: The Discovery of Pulsars Announced

"People on the Earth are not think that a region of the universe n 1967, when Jocelyn Bell, Within a few to resist. They became moving at the same speed as the from which no escape is possible, then a graduate student in weeks Bell noticed even more excited atomic clocks on the satellites." even in principle, is exciting?” Iastronomy, noticed a strange something odd in the when they learned that –Brett Taylor, Radford –Richard Price, University of “bit of scruff” in the data com- data, what she called a a woman was involved University, on why GPS systems Texas at Brownsville, on gravita- ing from her radio telescope, she bit of “scruff.” The in the discovery. Bell would not work without factoring tional waves and black holes, The and her advisor Anthony Hewish signal didn’t look later recalled the media in relativity, Roanoke Times, Brownsville Herald, December 14, initially thought they might have quite like a scintillat- attention in a speech December 28, 2005 2005 detected a signal from an extra- ing source or like about the discovery: “I terrestrial civilization. It turned manmade interfer- had my photograph “The discovery also explains "We can now go inside a [cell] out not be aliens, but it was still ence. She soon real- taken standing on a why this black hole is so bright in structure and see how it feels. We quite exciting: they had discov- ized it was a regular bank, sitting on a bank, standing on a bank X-rays. It's because the black hole are able to interact with the ered the first pulsar. They signal, consistently Jocelyn Bell ca. 1970 can pull gas directly off from the nanoworld." announced their discovery in coming from the same examining bogus outer layers of the giant star." –Gustavo Luengo, L’Oréal, on February 1968. patch of sky. records, sitting on a bank exam- –Philip Kaaret, University of powerful microscopes and probes Bell, who was born in Ireland No known natural sources ining bogus records. Meanwhile , on the discovery of a giant that allow him to view and poke in 1943, was inspired by her high would produce such a signal. Bell the journalists were asking rel- star orbiting a medium sized black individual atoms, Business Week, school physics teacher to study and Hewish began to rule out var- evant questions like was I taller hole, Associated Press, January 8, December 12, 2005 science, and went to Cambridge ious sources of human interfer- than or not quite as tall as 2006 to pursue her PhD in astronomy. ence, including other radio Princess Margaret, and how "I would argue that intelligent Bell’s project, with advisor astronomers, radar reflected off the many boyfriends did I have at a "It is very unpleasant to have a design is not science. When faced Anthony Hewish, involved using moon, television signals, orbiting time?” 5,000-pound instrument crash into with an organism, they say it's too a new technique, interplanetary satellites, and even possible effects Other astronomers were also your living room." complex to have appeared from scintillation, to observe quasars. from a large corrugated metal energized by the finding, and –Scott Nutter, Northern evolution. So they invoke divine Because quasars scintillate more building near the telescope. None joined in a race to discover more University, on why the intervention, and then they stop than other objects, Hewish of those could explain the strange pulsars and to figure out what cosmic ray detector instruments thinking. That's what intelligent thought the technique would be signal. these strange sources were. By had to be flown on balloons over design is. It's lazy thinking." a good way to study them, and The signal, a series of sharp the end of 1968, dozens of pul- an uninhabited area, Cincinnati –Rush Holt, US House of he designed a radio telescope to pulses that came every 1.3 sec- sars had been detected. Soon Enquirer, January 11, 2006 Representatives, Trenton Times, do so. onds, seemed too fast to be com- Thomas Gold showed that pul- December 22, 2005 Working at the Mullard Radio ing from anything like a star. Bell sars are actually rapidly rotating "Once you go down that road it Astronomy Observatory, near and Hewish jokingly called the neutron stars. Neutron stars were is very difficult to make a U-turn "As a scientist, I'd think some- Cambridge, starting in 1965 Bell new source LGM-1, for “Little predicted in 1933, but not detect- and go back to where you were," times it's good to have a little con- spent about two years building Green Men.” (It was later ed until the discovery of pul- –Mike Lubell, APS and CUNY, troversy to be sure what's being the new telescope, with the help renamed.) sars. These extremely dense on budget cuts that will cause lay- taught." of several other students. But soon they managed to rule stars, which form from the col- offs and cutbacks at RHIC, –Robert Kaita, Princeton Together they hammered over out extraterrestrial life as the source lapsed remnants of massive stars Associated Press, January 2, 2006 Plasma Physics Laboratory, 1000 posts, strung over 2000 of the signal, when Bell noticed after a supernova, have strong supporting intelligent design, dipole antennas between them, another similar signal, this time a magnetic fields that are not “Black hole processes are per- Trenton Times December 22, and connected it all up with 120 series of pulses arriving 1.2 seconds aligned with the star’s rotation haps the most exciting source of 2005 miles of wire and cable. The fin- apart, coming from an entirely dif- axis. The strong field and rapid gravitational waves. Don’t you Members in the Media contiued on page 4 ished telescope covered an area ferent area of the sky. It seemed rotation produces a beam of radi- of about four and a half acres. quite unlikely that two separate ation that sweeps around as the They started operating the tel- groups of aliens were trying to star spins. On Earth, we see this escope in July 1967, while con- communicate with them at the as a series of pulses as the neu- struction was still going on. Bell same time, from completely differ- tron star rotates, like a beam of had responsibility for ent locations. Over Christmas light from a lighthouse. operating the telescope and ana- 1967, Bell noticed two more such After discovering the first Don’t Give Me No Bad News! lyzing the data–nearly 100 feet bits of scruff, bringing the total to pulsars, Jocelyn Bell finished of paper every day–by hand. She four. her analysis of radio sources, By Michael S. Lubell, APS Director of but, until recently, the West Wingers soon learned to recognize By the end of January, Bell and completed her PhD, got married Public Affairs just didn’t get the idea that “Science scintillating sources and Hewish submitted a paper to and changed her name to You don’t have to be a soldier in and Technology” is not an American interference. Nature describing the first pulsar. Burnell. She left radio astrono- Iraq to know that the world is filled protectorate. They’ve been so In February, a few my for gamma ray astronomy with mines. And not all of them are focused on their rosy optimism they days before the paper and then x-ray astronomy, improvised explosive devices, con- haven’t seen the mines ahead or the was published, though her career was hindered cealed and instantly lethal. No, the enemies behind. For them, “It’s Hewish gave a semi- by her husband’s frequent moves ones I have in mind are visible, and morning in America!” is more than nar in Cambridge to and her decision to work part they pack a delayed charge, one a Reagan campaign slogan–it’s the announce the discov- time while raising her son. that can cripple America the mighty. reality. Would that it were true. ery, though they still Anthony Hewish won the Nobel You have to have your eyes shut, Yes, we lead the world in entre- had not determined the Prize in 1974 for the discovery your ears plugged or your entire preneurs and venture capitalists. We nature of the source. of the first pulsars. Over 1000 head in the sand not to know they’re have the strongest banking The announcement pulsars are now known. there. But that’s just about how the system, the best protection of intel- caused quite a stir. The As for little green men, they White House has behaved for the lectual property rights and the great- press jumped on the haven’t been found yet, but proj- last five years when it comes to the est graduate institutions. But we story–the possible ects such as the Search for Extra high tech challenges our country is also have one of the poorest per- finding of extraterres- Terrestrial Intelligence (SETI) facing from abroad. formance records in elementary and Artist's rendering of a pulsar trial life was too hard are still looking for them. Call it arrogance or ignorance, Inside the Beltway continued on page 11

Series II, Vol. 15, No.2 Department, American Physical Society, One Physics Ellipse, Treasurer Physics and Society), J. H. Eberly (Laser Science), February 2006 College Park, MD 20740-3844, [email protected]. Thomas McIlrath*, University of Maryland (emeritus) Leonard Feldman (Materials), Akif Balantekin (Nuclear), APS NEWS ©2006 The American Physical Society Editor-in-Chief John Jaros* (Particles & Fields), Ronald Ruth (Physics For Nonmembers–Circulation and Fulfillment Division, Martin Blume*, Brookhaven National Laboratory of Beams), James Drake* (Plasma), Timothy Lodge American Institute of Physics, Suite 1NO1, 2 Huntington (emeritus) (Polymer Physics), Gianfranco Vidali, ( Section), Coden: ANWSEN ISSN: 1058-8132 Quadrangle, Melville, NY 11747-4502. Allow at least 6 Past-President Paul Wolf ( Section) Editor ...... Alan Chodos weeks advance notice. For address changes, please send both Marvin L. Cohen*, University of California, Berkeley Associate Editor ...... Jennifer Ouellette the old and new addresses, and, if possible, include a mail- General Councillors ADVISORS Staff Writer ...... Ernie Tretkoff ing label from a recent issue. Requests from subscribers for Christina Back, Janet Conrad, Wendell Hill, Evelyn Hu*, Representatives from Other Societies Special Publications Manager ...... Kerry G. Johnson missing issues will be honored without charge only if received Ann Orel, Arthur Ramirez, Richart Slusher, Laura Smoliar* Kenneth Heller, AAPT; Marc Brodsky, AIP Design and Production ...... Amera Jones within 6 months of the issue’s actual date of publication. International Councillor International Advisors Forefronts Editor ...... Craig Davis Periodical Postage Paid at College Park, MD and at addition- Albrecht Wagner María Esther Ortiz, Mexican Physical Society, Proofreader ...... Edward Lee al mailing offices. Postmaster: Send address changes to APS Chair, Nominating Committee Walter Davidson, Canadian Association of Physicists APS News (ISSN: 1058-8132) is published 11X the right to select and to edit for length or clarity. All corre- News, Membership Department, American Physical Society, Thomas Rosenbaum yearly, monthly, except the August/September issue, by spondence regarding APS News should be directed to: Editor, One Physics Ellipse, College Park, MD 20740-3844. Chair, Panel on Public Affairs Staff Representatives the American Physical Society, One Physics Ellipse, APS News, One Physics Ellipse, College Park, MD 20740- Alan Chodos, Associate Executive Officer; Amy Flatten College Park, MD 20740-3844, (301) 209-3200. It 3844, E-mail: [email protected]. APS COUNCIL 2006 Division, Forum and Section Councillors Director of International Affairs; Ted Hodapp, Director contains news of the Society and of its Divisions, President Charles Dermer (Astrophysics), Kate Kirby* (Atomic, of Education and Outreach; Michael Lubell, Director, Topical Groups, Sections and Forums; advance Subscriptions:APS News is an on-membership publication John J. Hopfield*, Princeton University Molecular & Optical Physics) Robert Eisenberg (Biological), Public Affairs; Stanley Brown, Editorial Director; Charles information on meetings of the Society; and reports to delivered by Periodical Mail. Members residing abroad may President-Elect Charles S. Parmenter (Chemical), Moses H. Chan Muller, Director, Journal Operations; Michael Stephens, the Society by its committees and task forces, as well receive airfreight delivery for a fee of $15. Nonmembers: Leo P. Kadanoff*, University of (Condensed Matter Physics), Richard M. Martin Controller and Assistant Treasurer as opinions. Subscription rates are available at http://librarians.aps.org/ Vice-President (Computational), Harry Swinney* (Fluid Dynamics), Peter institutional.html. Arthur Bienenstock*, Zimmerman (Forum on Education), Roger Stuewer (Forum Letters to the editor are welcomed from the member- Executive Officer on History of Physics), Patricia Mooney* (Forum on Administrator for Governing Committees ship. Letters must be signed and should include an Subscription orders, renewals and address changes should Judy R. Franz*, University of , Huntsville Industrial and Applied Physics), David Ernst (Forum on Ken Cole address and daytime telephone number. The APS reserves be addressed as follows: For APS Members–Membership (on leave) International Physics), Philip “Bo” Hammer* (Forum on * Members of the APS Executive Board APS NEWS February 2006 3

Scientists, Teachers, Clergy Hail Court Ruling Scientists and nonscientists doctrines in the classroom, and alike applauded a US district would dramatically weaken By Ernie Tretkoff Duke drifted into a variety of court ruling in December that a American science education," Ed. Note: With this article we research and management posi- school board violated the said Ken Miller, a Brown inaugurate an occasional series of tions, simply by taking charge Constitution by requiring high University biology professor who profiles of physicists with careers and doing what needed to be school science students to learn is the author of widely-used high in industry. done. He has managed research about "intelligent design," the school biology textbooks. Over his long and successful groups of various sizes and has idea that living species formed The decision will improve K- career as an industrial physicist, recently retired as Vice President through the intervention of a 12 science education and there- Charlie Duke has watched indus- and Senior Research Fellow of supernatural designer. The deci- by help the US stay competitive try change dramatically and now Xerox Innovation Group. sion shows that the US will main- in science and technology, said sees industry moving into a new era Having worked in both industry tain a strong science curriculum, Marshall Berman, a retired gov- in which the must and academia, Duke has noticed which will help the US stay com- ernment scientist who has served struggle to keep up in a global quite a difference between the two petitive in science and technolo- as vice president for the New economy. environments. “The successful per- gy, experts say. According to oth- State Board of Education. Duke originally went into son at a university is an independ- ers, the decision underlines that "The US is falling rapidly and physics somewhat by chance. He ent businessman. You get your Photo credit: Ernie Tretkoff Charlie Duke intelligent design is a disguised drastically behind other countries started out in college in 1955 at grant, and you run your show. form of religious creationism, in science and math education," Duke University as a religion You’re like a small businessman. existed inside Xerox,” says Duke. one that is promoted by organized Berman says. Without a much major, intending to become a min- No one tells you what to do or how But that would never happen nowa- public-relations strategies instead stronger focus on science, "US ister. After his junior year he real- to do it. It’s every man for him- days. “You would now have differ- of research in scientific journals. competitiveness is almost cer- ized it wasn’t for him. He switched self.” ent pieces done in different places,” The US District Court in tainly destined to be second- his major to mathematics, but his Industry is the opposite extreme, says Duke. Harrisburg, ruled class," he says. The decision, says roommate happened to be a physics says Duke. “When a young person A threat that Duke worries about that the York County (PA) school Berman, makes very good sense major, so Duke took some gradu- comes to work for Xerox, they are now is globalization. The United board violated the Constitution's economically, scientifically and ate level physics courses, and found put into a project. They are told States is facing increased competi- principle to separate government constitutionally. It sends the mes- he excelled in them. Professors what to do. They work on a sched- tion from other counties, including and religion by requiring a sage that the US is focused on pushed him to go on to graduate ule. Their resources are largely and , which are rapidly four-paragraph statement to be better science education. school, and he did. beyond their control.” becoming technologically advanced read to high-school science stu- Berman's back page article on After completing his PhD at The social environments are and have an enormous supply of dents. The statement attacked the subject in the October 2005 Princeton University in 1963, Duke very different, as well, he says. At cheap, educated labor. China pro- evolution, the cornerstone of APS News helped keep ID out of found that physicists were very a university, people socialize with duces more engineers a year than we modern biology, and promoted classrooms in the Minnetonka much in demand in industrial labs. others in their department. But not have in the entire country, Duke points intelligent design as an alterna- school district in . “Sputnik had happened, and every- in industry. “There is very little out. The United States is in danger of tive to evolution. Carol Eastlund, a school board one was recruiting physicists,” he social life at Xerox. It’s a very hier- falling behind in science and tech- Judge Jones wrote in his deci- member, quoted from Berman's recalls. “I was in demand, to my archical structure. If you’re a boss, nology. sion, "We hold that the ID Policy article in her remarks to the utter shock.” you have power over people. So As this happens, more and more is unconstitutional pursuant to Minnetonka Board of Education Duke started his career in indus- it’s not appropriate to socialize too jobs will be outsourced, Duke pre- the Establishment Clause of the in December. try as a staff researcher at General much. It’s intensely competitive,” dicts. (He even commented that APS First Amendment of the United Despite arguments to the con- Electric in 1963. From 1969 to says Duke, “That was one of my could save money by having this arti- States Constitution and Art. I, trary, evolution and religion can 1972 he was a professor of physics biggest shocks.” cle written by someone in Mongolia Section 3 of the Pennsylvania co-exist harmoniously, some at the University of . He In industry, the focus is always instead of here in College Park, Constitution." clergy members say. joined Xerox Corporation in 1972 on producing a valuable product Maryland) "History shows that attempts "There is no conflict between as a scientist in the materials for the customer, unlike in the uni- “The pace of change is speeding to push creationism in the public evolution and belief in God, but research section, and has been at versity, where research can be large- up and the US is falling further and schools don't go away, they just evolution belongs in the science Xerox in various positions since ly curiosity-driven. Duke clearly further behind,” says Duke. “It’s a adapt to the legal circumstances," classroom and theology, biblical then. thinks in terms of economic value big deal. It makes the fall of the large said Eugenie Scott, Executive or not, belongs in philosophy or Even though a career in physics all the time. Giving customers prod- industrial labs look like a pin prick.” Director, National Center for religious discussions," said wasn’t his original plan, Duke has ucts they value is the most impor- Duke doesn’t claim to have a solu- Science Education, which mon- Charles W. Holsinger, an been extremely successful. He has tant consideration. “If you don’t tion, but he is certain that the coun- itors intelligent design activity ordained Presbyterian minister been elected to the National get the product out, then the com- try is not paying enough attention to in the US "It is already clear that who lives in Seven Valleys, Academy of Sciences and the pany doesn’t survive, so there is a the looming threat. “The US govern- the new slogan for the ID move- Pennsylvania, in southern York National Academy of Engineering, lot more intensity at an industrial ment in my view is just distracted. ment is going to be ‘Teach the County. "Belief in God should has won several prestigious prizes, organization.” The war in Iraq is a side show. This Controversy!’– even though there not stifle curiosity and research including most recently the 2006 Over the course of his career, country is running on empty,” he says. is no scientific controversy over by assuming God is the answer to APS George E. Pake Prize. “That Duke has seen major changes in “ People blow up cars in Baghdad, the validity of evolution in anything. The miracle and won- just goes to show that if you are industry. Between the end of and that gets a lot of press coverage, biology." der of the natural world, includ- determined and persistent you can World War II and the end of the but when you look at the global "Calls to 'teach both sides' of ing evolution, led me to believe do something.” he says. Cold War, large companies owned economy, that’s the end of a controversy that does not exist in a God.” When he started at Xerox in enormous industrial research lab- life as the American middle class would lead to the inclusion of –Courtesy of Inside Science 1972, Duke’s research focused on oratories, such as ATT’s Bell Labs, knows it.” non-scientific and anti-scientific News Service the electronic structure of molec- General Electric’s research lab in ular solids. Models he developed Schenectady, NY, and Xerox’s Palo TAIWAN SYMPOSIUM CONTINUED FROM PAGE 1 helped enable Xerox to produce Alto Research Center. During this flexible organic photoconducting era, industry operated on a “closed cultural evening, sightseeing tours people and their families. about how wonderful it was and belts that could be wrapped around innovation” model, in which every in Taipei and the surrounding area, Participants earned points by com- how inspired they were to do more small rollers to enable high speed step of the value chain –from con- and an awards ceremony honoring pleting projects related to physics, physics.” photocopying with small machines. ception of an idea, to research and the students’ achievements in such as writing an essay, doing a The US students who The polymer belts helped create development, to manufacture of a physics. physics experiment, visiting a participated in the Physics Young billions of dollars in revenue and product and sales and customer “The symposium in Taiwan was physics lab, or attending a World Ambassador’s symposium were: helped the Xerox company to sur- support–was done within a single the most exciting event I have ever Year of Physics event. The talent Franz Sauer vive after it was forced to allow company. participated in. From meeting search was intended to be inclu- High Technology High School other companies to use its patents But since the end of the Cold famous physicists to discussing sive, not competitive, said Gavrin. Lincroft, in 1975. War, the large industrial labs have physics subjects with students from Students who earned 10 points “Organic photoconductors collapsed. Now, information flows all over the world, it will forever were recognized as “United States Kelsey Duncan turned out to be the essential inno- more freely between different com- influence my love of physics and Physics Talent.” Higher numbers of J.P. McConnell Middle School vation that allowed the company to panies, between industry and uni- has convinced me that I want to points earned students Loganville, Ga. survive,” he says. “Applying the versities, and across national bound- study physics in college,” said “International Honorable Mention” Amy Abramowitz physics of how charges go through aries. Industry now operates on an Franz Sauer, one of the US physics awards. The girl and boy in each Myers Park High School polymers was one of many things “open innovation” model, in which young ambassadors. age group with the most points Charlotte, NC that made it possible. The research different parts of the About 300 students participated became “Physics Young was a vital part of the third gener- innovation process happen at in the United States Physics Talent Ambassadors,” and were invited Daniel Duncan ation of xerographic technology.” different places. Companies partner Search, according to US organizer to attend the symposium in Taiwan. Millburn School Duke has also conducted with researchers in other Andrew Gavrin of Indiana The symposium and the talent Wadsworth, IL research on other topics, includ- companies, in universities, and in University-Purdue University search helped students understand (also Antioch Community High ing electron tunneling, semicon- other countries. Indianapolis. The talent search ran what physics is about, and encour- School, Antioch, IL) ductor surface structure, tunneling “When I did research on organ- during 2005 as a way to create aged the students to continue learn- Alexandra Vinegar in solids, and inelastic scattering of ic materials that got turned into a enthusiasm, interest, and partici- ing about physics, said Gavrin. Chapel Hill High School low-energy electrons in solids. product, that whole value chain pation in physics among young “Every one of them said something Chapel Hill, NC 4 February 2006 APS NEWS Letters Berman's Back Page Defended Marshall Berman's call to arms ments as the source of all the furor, New Website Lets Visitors Assess “Female-friendliness” against the pernicious doctrine of has misconstrued an effect as the creationism ("Back Page", October, cause. of Graduate Departments 2005) deserves more support than Edward J. Garboczi's fatuous By Marc Sher critical in their career development. tenured faculty – male/female? it receives in the December, 2005 suggestion that scientists should key date for Graduate Yet how are students to learn 2. How many graduate stu- Letters. ignore all statements by religious Admissions Directors is about the climate, especially the cli- dents?– male/female? Creationist attacks on the believers raises the question of why AApril 15th. In addition to mate for women? Web pages gen- 3. Is there a family leave policy theory of evolution, arising because many who accept the scientific being the federal tax deadline, it is erally give very little information for graduate students? If so, describe. of its incompatibility with a literal pronouncements of, for example, the date by which admitted students and faculty advisors typically know 4. Is there family health insurance interpretation of the early chapters Newton reject his religious beliefs. must commit to attending their a few people at the institution and available for graduate students? Is of Genesis, stir up a wide range of The answer of course is that choice of graduate schools. Between can only comment about the it included in the stipend? scientific defenders, some of whom observational and experimental sup- now and then, undergraduate seniors research. The campus visits for 5. In a paragraph, please describe overstate their case by assigning to port is offered for the former but not (and those reentering physics) will admitted students are often (but not why someone applying to graduate evolutionary theory a greater for the latter. be scouring web pages, talking to always) highly scripted affairs (“dog school who is interested in a female- certainty than it merits. So J. W. John G. Fletcher friends, faculty and advisors, and and pony shows”), on weekends, in friendly department should choose Lane, in identifying these overstate- Livermore, CA visiting campuses. which only current students with your institution. What are the key factors in this positive things to say meet with the The first two questions are sim- Science Reporting or Junk Writing? decision? There is much more to a prospective students. ple demographics. The next two are graduate school that the quality of As a member of the APS designed to give students a good I read with amused distress the whom the money comes) will be the research. Graduate departments Committee on the Status of Women idea as to whether female-friendly two articles "Living the (Scientific) impressed to dip into their (i.e. the are communities in which young in Physics (CSWP), I was interest- policies are already in place (as a American Dream" and "Science public's) pockets, is very doubtful. adults will spend 5-6 years of their ed in giving prospective students a result of the survey, several chairs matters at USA Today" in your When I was very young, in lives. The probability of success better idea of the climate for women have told me that they hope to insti- November 2005 issue. The first, communist Hungary, I occasional- depends in large part on the atmos- at graduate institutions. Of course, tute such policies at their institu- with dramatic verve, the second, ly acted as a science writer to sup- phere in the department We’ve all making a list of problem institutions tions). The final question is much with lyrical eloquence, assures us plement my meager and uncertain heard horror stories of institutions would not be appropriate (certain- more open-ended. that is is possible to become a sin- income as an assistant professor. with unfriendly climates, in which ly not under the APS rubric). Instead, The response rate was extraordi- gle universal genius who upon I remember the agony (not ela- students are treated poorly and with- an e-mail was sent to the chairs of nary. With just an e-mail and one fol- need and command is capable of tion!) I went through when I had out much respect. For women espe- roughly two hundred graduate insti- low-up, we now have had respons- writing meaningful, nay, inspir- to write about a topic which, cially, attending a school with a tutions which asked five questions: es from the chairs, or their designees, ing reports on all scientific top- though in my field of theoretical warm and nurturing climate can be 1. How many tenure-track or Female friendly continued on page 11 ics, from quark confinement to physics, was not really in my area laser technology, from polymer of active competence. But then, World Year of Physics Just the Beginning science to molecular genetics, etc., this was almost 60 years ago. all the way to cosmology. Standards are now different. By Alan Chodos World View, celebrating Einstein’s have heard anything about the World To achieve such a feat, one If we want to (as we must) mid the revelry this past New achievements; details can be seen at Year of Physics, the answer will ought to be something like make young people and the mys- Year’s Eve, the World Year www.physicsmatters.org. almost certainly be no. Lavoisier, Darwin, Planck, terious "public" more conscious Aof Physics quietly passed into Those are some of the highlights. The good news is that therefore Einstein, Heisenberg, Crick, of the role which science plays in history. It’s worth taking a few I’m pleased to say that APS is extend- there is much opportunity for addition- Hubble etc. combined. This can- humanism and society, we must moments to review what was accom- ing PhysicsQuest as an ongoing annu- al public outreach. The World Year of not be achieved by human beings, find better methods than propa- plished, and to look ahead to the great al project. Einstein@home and Adopt- Physics was a valuable springboard not even if they are supported by ganda journalism. I became a sci- deal that still needs to be done. a-Scientist are continuing, and we to get the physics community more the APS. The outcome of such an entist because first, my father APS took the lead in promoting hope A New World View will have a engaged with the public. But the effort enterprise is at best a hotchpotch, inspired me; and second, because WYP activities throughout the US. lasting impact as well. But as David has barely taken off, and we need to mixed with PR publicity propa- when I was 10, I asked for and got One of our most important tasks was Harris points out in the January issue continue to be creative and proactive ganda, "gee-whiz" show biz, as a chemistry set for Christmas. It simply to get the word out to the of Symmetry, all of these efforts, in a as we tell the story of the importance we are, sadly, accustomed to from was only after that that I started physics community nationwide, and country the size of the US, cannot and excitement of physics. our papers and journals. Even read- reading well-written, single-topic we’re pleased to note that over 600 compete for very much of the atten- As the Associate Executive Officer ing editorial short-reviews pub- popular science books – the few events were recorded on our event tion of the average citizen. If you stop of APS, Alan Chodos was heavily lished in Physics Today, one some- which then existed both in my finder at www.physics2005.org ; since a random person in the street (or even involved in the Society’s World Year times feels that the reporter went mother tongue and foreign lan- not all events found their way to our on a university campus) and ask if they of Physics activities. beyond his ken and did not quite guages. And finally, I had a well- event finder, this probably means that understand the topic. versed scientist as my physics and there were in the neighborhood of More importantly, such junior- math teacher in senior high school. 1000 outreach events organized at Einstein and the World Year of Physics high-school-science-inspired arti- (Eventually he became a professor the local level under the rubric of the cles may entice inquisitive kids to at the University and I got my PhD World Year of Physics. "take up science", but finding out under his guidance.) Nowadays With funding from the NSF, the that this requires specific concen- we indulge our children with TV's, DOE’s Office of Science, and NIST, tration and that miracles are rare, computer games, cell-phones. APS also organized its own WYPproj- they will soon drop it. (I have Something is wrong here. ects. Two of them were aimed specif- examples of this even in my fam- Paul Roman ically at schools: the Eratosthenes proj- ily.) And whether politicians (from Ludenhausen, ect for high schools, for which over 700 high school classrooms signed up in the spring of 2005; and the MEMBERS IN THE MEDIA CONTINUED FROM PAGE 2 PhysicsQuest project for middle "The world is not as real as we carry us only so far." schools, which garnered about 5000 think. My personal opinion is that –Philip Kuekes, Hewlett- participating classrooms in each of the the world is even weirder than what Packard Laboratories, on the spring and fall semesters of 2005. quantum physics tells us." switch from silicon technology to In addition, we were able to devote –Anton Zeilinger, University of nanotechnology, The New York $200,000 to finance 20 “Physics on Vienna, on quantum weirdness, Times, December 29, 2005 the Road” teams across the country. The New York Times, December We had to choose from among close 27, 2005 "If this equation were found to to 40 excellent applications, and we be even slightly incorrect, the were reminded of the tremendous tal- The fact that the World Year of Physics celebrated the centenni- “Astronomers wanted a time impact would be enormous - given ent and enthusiasm for this kind of out- al of Einstein’s miracle year turned out to be a mixed blessing. On scale that represented the Earth's the degree to which [it] is woven reach that can be unleashed with a the positive side, since more people have heard of Einstein than have movement, and the clock commu- into the theoretical basis of modern small amount of financial support. any idea what physics is all about, it was frequently possible to use nity wanted a smooth scale. The physics and everyday applications. We also helped to launch Einstein as a way of beginning a conversation about physics. compromise has become increas- This doesn't mean [the relation] “Einstein@home,” a project with real The downside is that all too often the conversation stopped with ingly difficult to maintain." has been proven to be completely scientific potential, that uses data from Einstein. Much of the media attention naturally focused on the man –Judah Levine, NIST/University correct. Future physicists will LIGO and GEO to search for gravi- with the deep-set eyes and untamed hair. Many of the public events of , on leap seconds, The undoubtedly subject it to even more tational waves. Alas, gravitational concentrated more on Einstein’s achievements than on the promise Washington Post, December 26, precise tests because accurate waves were not found in 2005, but the of new discoveries. 2005 checks imply that our theory of the project continues and the search goes Einstein of course deserved the accolades he received. But to world is in fact more and more on. We sponsored an “Adopt-a- become a physicist or to be interested in understanding the physi- "In between 2003 and 2005 complete." Scientist” program that brings high cal world one doesn’t necessarily have to be an Einstein. Despite there has been a tipping point. All –David Pritchard, MIT, on precise school classes into contact with sci- our best efforts, that message, important to students and the public of the buzz is about nanotechnol- tests of E=mc2, Christian Science entists in industry and academia. We alike, did not always get through. –A.C. ogy. The physics of silicon can Monitor, December 29, 2005 commissioned a work of art, ANew APS NEWS February 2006 5

A Supplement to APS News Edited by Phillip F. Schewe, Ben Stein and Ernie Tretkoff

INTRODUCTION THE BIGGEST SPLASH OF LIGHT FROM OUTSIDE Physics News in 2005, a summary of physics highlights for the past year, was com- THE SOLAR SYSTEM piled from items appearing in AIP’s weekly newsletter Physics News Update, written The biggest splash of light from outside the solar system to be record- by Phil Schewe and Ben Stein. The items in this supplement were compiled by Ernie ed here at Earth occurred on December 27, 2004. The light came from Tretkoff of the American Physical Society. The items below are in no particular order. an object called SGR 1806-20, about 50,000 light years away in our own Because of limited space in this supplement, some physics fields and certain contri- galaxy. SGR stands for “soft gamma repeater,” a class of neutron star butions to particular research areas might be underrepresented in this compendium. possessing a gigantic magnetic field. Such “magnetars” can erupt vio- These items mostly appear as they did during the year, and the events reported there- lently, sending out immense bolts of energy in the form of gamma rays in may in some cases have been overtaken by newer results and newer publications and light at other wavelength regions of the electromagnetic spectrum. which might not be reflected in the reporting. Readers can get a fuller account of the The eruption was first seen with orbiting telescopes at the upper end of Credit: G.B. Taylor, NRAO/AUI/NSF) year’s achievements by going to the Physics News Update website at the spectrum over a period of minutes and then by more and more tel- http://www.aip.org/physnews/update and APS’s Physical Review Focus website at escopes; at radio wavelengths emissions were monitored for months. For an instant the flare http://focus.aps.org/. was brighter than the full moon. (NASA press conference, 18 February; www.nrao.edu/pr/2005/sgrburst/; many telescopes participated in the observations, reports AN OCEAN OF QUARKS appeared in the 28 April 2005 issue of Nature.) Nuclear physicists have demonstrated that the material essence of the universe at a time SUPERFLUID SOLID HYDROGEN mere microseconds after the big bang consists Last year Moses Chan (Penn State) announced the results of an experiment in which of a ubiquitous quark-gluon liquid. This insight solid helium-4 was revolved like a merry-go-round. It appeared that when the bulk was comes from an experiment carried out over the revolved at least part of the solid remained stationary. In effect part of the solid was pass- past five years at the Relativistic Heavy Ion ing through the rest of the solid without friction. Chan interpreted this to mean that a Collider (RHIC) at Brookhaven National Lab, fraction of the sample had become superfluid. where scientists have created a toy version of the Now, Chan sees evidence for superfluid behavior in solid hydrogen as well. Speaking cosmos amid high-energy collisions. RHIC is, in at the March meeting of the American Physical Society in Los Angeles, Chan said that his effect, viewing a very early portion of the uni- Courtesy of Brookhaven National Laboratory hydrogen results are preliminary and that further checks are needed before ruling out verse, before the time when protons are thought alternative explanations. The concept of what it means to be a solid, Chan said, needs to to have formed into stable entities (ten microseconds after the big bang). be re-examined. In our later, cooler epoch quarks conventionally occur in groups of two or three, held together by gluons. Could a nucleus be made to rupture and spill its innards into a common swarm of unconfined quarks and gluons? This is what RHIC DIRECT DETECTION OF EXTRASOLAR PLANETS set out to show. Direct detection of extrasolar planets has been achieved for the first In the RHIC accelerator two beams of gold ions are clashed at several interac- time. Previously the existence of planets around other suns has been tion zones around the ring-shaped facility. Every nucleus is a bundle of 197 pro- inferred from subtle modulation of the light emitted by the star. Now tons and neutrons, each of which shoots along with an energy of up to 100 GeV. light from the planet itself has been recorded directly at infrared wave- When the two gold projectiles meet in a head-on “central collision” event, the total lengths by the Spitzer Space Telescope (www.spitzer.caltech.edu). collision energy is 40 TeV. Of this, typically 25 TeV serves as a stock of surplus The planets, one with the prosaic name of HD 209458b (153 light energy–call it a fireball–out of which new particles can be created. Indeed in years away), the other TrES-1 (489 light years away), orbit their stars many gold-gold smashups as many as 10,000 new particles are born of that fire- more tightly than does Mercury around our sun. This makes the Jupiter- sized planets hot enough to be viewed by Spitzer. (NASA press confer- Credit:: NASA/JPL- ball. Caltech/R. Hurt (SSC)) The outward-streaming particles provided the tomographic evidence for deter- ence, 23 March; report published in Nature, 7 April.) mining the properties of the fireball. The recreation of the frenzied quark era lasts only a few times 10-24 seconds. The size of the fireball is about 5 femtometers, ZEPTOGRAM MASS DETECTION–WEIGHING MOLECULES its density about 100 times that of an ordinary nucleus, and its temperature about Michael Roukes and his Caltech colleagues have performed mass measurements with near- 2 trillion degrees Kelvin or 175 MeV. But was it the much-anticipated quark-gluon ly zeptogram (zg) sensitivity, that is, with an uncertainty of only a few times 10-21 grams. At plasma? The data unexpectedly showed that the fireball looked nothing like a gas. this level one can start to weigh molecules one at a time. In experiments, the presence of xenon For one thing, potent jets of mesons and protons expected to be squirting out of accretions of only about 30 atoms (7 zg, or about 4 kilodaltons, or the same as for a small the fireball were being suppressed. protein) have been detected in real time. For the first time since starting nuclear collisions at RHIC in the year 2000 and Minuscule masses are measured through their effect on an oscillating doubly clamped sil- with plenty of data in hand, all four detector groups operating at the lab have con- icon carbide beam, which serves as the frequency-determining element in a tuned circuit. In verged on a consensus opinion. They believe that the fireball is a liquid of strong- practice, the beam would be set to vibrating at a rate of more than 100 MHz and then would ly interacting quarks and gluons rather than a gas of weakly interacting quarks and be exposed to a faint puff of biomolecules. Each molecule would strike the beam, where its gluons. The liquid is dense but seems to flow with very little viscosity, approxi- presence (and its mass) would show up as a changed resonant frequency. mating an ideal fluid. The RHIC findings were reported at the April meeting of After a short sampling time, the molecule would be removed and another brought in. Through the American Physical Society in Tampa. this kind of miniaturization and automation, the NEMS approach to mass spectroscopy could Papers published concurrently by the four groups: BRAHMS: Nucl.Phys. A change the way bioengineering approaches its task, especially in the search for cancer and 757 (2005) PHENIX: 1-27, Nucl.Phys. A 757 (2005) 28-101, PHOBOS: Nucl.Phys. its causes. The Roukes group reported its findings at the APS March Meeting in Los Angeles. A 757 (2005) 102-183, STAR Nucl. Phys. A 757 (2005) 184-283 NO SPLASH ON THE MOON THE MOST DISTANT CRAFT LANDING IN THE SOLAR SYSTEM Sidney Nagel’s lab at the University of Chicago has The Huygens probe, given long passage by the Cassini explored the behavior of liquid drops when they fall from spacecraft into the middle of Saturn’s minor planetary system, a faucet. At the APS March meeting, Nagel’s graduate stu- has successfully parachuted onto the surface of Titan, the dent, Lei Xu, revealed a surprising discovery concerning only moon with a considerable atmosphere. Pictures taken one of the commonest physical effects: the splash a liq- from miles above the surface during the descent and pictures uid drop makes when it strikes a flat surface. taken on the surface itself suggest the presence of boulders Under ordinary atmospheric conditions a liquid drop or ice chunks and some kind of shoreline, perhaps of a hydro- will flatten out on impact, splay sideways, and also raise carbon lake or sea. The data gained so far include a sort of a tiara-like crown of splash droplets. Remove some of the ambient atmosphere, and surprising- acoustic sampling of the atmosphere during the descent and ly the splash becomes less. At about one-fifth atmosphere the splash disappears altogether, leav- some color photographs. The Titan probe is named for ing the outward going splat but no upwards splash. Apparently it is the presence of the air mol- Christiaan Huygens, who first spotted Titan and who also ecules that give the impacting liquid something to push off of; remove the surrounding atmos- was the first to provide the proper interpretation of Saturn’s ring system. phere, and the splash disappears. (Lei Xu, Wendy W. Zhang, and Sidney R. Nagel, Phys. Rev. (http://www.esa.int/SPECIALS/Cassini-Huygens/) Lett. 94, 184505, 2005) 6 February 2006 APS NEWS

PYROFUSION: A ROOM-TEMPERATURE, PALM-SIZED liquid form: in the gas phase (with a material density similar to that of the interstellar medi- um), inter-atomic scattering is simpler; furthermore, the strength of the pairing interaction NUCLEAR FUSION DEVICE can be tuned at will using an imposed external magnetic field. A room-temperature, palm-sized nuclear fusion device has been The ultracold lithium gas represents, in a narrow sense, the first “high-temperature” super- reported by a UCLA collaboration, potentially leading to new kinds of fluid. Consider the ratio of the critical temperature (T ) at which the superfluid transition fusion devices and other novel applications such as microthrusters for c takes place to the fermi temperature (T ), the temperature (or energy, divided by Boltzmann’s MEMS spaceships. f constant) of the most energetic particle in the ensemble. For ordinary superconductors, T /T The key component of the UCLA device is a pyroelectric crystal, a c f is about 10-4; for superfluid helium-3 it is 10-3; for high-temperature superconductors class of materials that includes lithium niobate, an inexpensive solid that 10-2; for the new lithium superfluid it is 0.3. (Zwierlein et al., Nature, 23 June 2005) is used to filter signals in cell phones. When heated, a pyroelectric crys- tal polarizes charge, segregating a significant amount of electric charge near a surface, leading to a very large electric field there. In turn, this ULTRAVIOLET FREQUENCY COMB effect can accelerate electrons to relatively high (keV) energies. Physicists at JILA, the joint institute of NIST and the University of Colorado, have cre- The UCLA researchers (Brian Naranjo, Jim Gimzewski, Seth Putterman) take this idea ated a new optical process to extend the production of coherent radiation into the extreme and add a few other elements to it. In a vacuum chamber containing deuterium gas, they ultraviolet region of the electromagnetic spectrum. This process takes advantage of the fact place a lithium tantalate (LiTaO3) pyroelectric crystal so that one of its faces touches a cop- that ultrafast laser pulses of femtosecond widths, separated by nanoseconds, manifest per disc which itself is surmounted by a tungsten probe. They cool and then heat the crys- themselves as a superposition of light at different frequencies over a wide spectral band. tal, which creates an electric potential of about 120 kilovolts at its surface. The Fourier transform of these short pulses is a long series of evenly spaced spikes that The electric field at the end of the tungsten probe tip is so high (25 V/nm) that it strips look like the tines of a comb. The JILA researchers have pushed the coverage of the fre- electrons from nearby deuterium atoms. Repelled by the positively charged tip, and crys- quency comb into the extreme ultraviolet by generating a series of high harmonics of the tal field, the resulting deuterium ions then accelerate towards a solid target of erbium deu- original, near-infrared laser frequency comb. (A comparable result has also been achieved teride (ErD2), slamming into it so hard that some of the deuterium ions fuse with deuteri- by Ted Hänsch’s group in Munich.) um in the target. Each deuterium-deuterium fusion reaction creates a helium-3 nucleus and In the JILA experiment, 50-femtosecond-long pulses, spaced 10 nanoseconds apart, are a 2.45 MeV neutron, the latter being collected as evidence for nuclear fusion. In a typical sent into a coherent storage device–an optical buildup cavity. The cavity length is deter- heating cycle, the researchers measure a peak of about 900 neutrons per second, about 400 mined so that each tine of the incoming frequency comb is matched to a respective cavity times the “background” of naturally occurring neutrons. During a heating cycle, which could resonance mode. In other words, the pulse train is matched exactly into the cavity such that last from 5 minutes to 8 hours depending on how fast they heat the crystal, the researchers a pulse running around inside the cavity is reinforced by a steady stream of incoming estimate that they create approximately 10-8 joules of fusion energy. By using a larger tung- pulses. After a thousand roundtrips through the cavity, the infrared laser light becomes suf- sten tip, cooling the crystal to cryogenic temperatures, and constructing a target contain- ficiently energized to directly ionize xenon atoms inside the cavity. The quick repatriation ing tritium, the researchers believe they can scale up the observed neutron production 1000 of the xenon electrons to their home atoms produces light pulses of high frequency har- times, to more than 106 neutrons per second. (Naranjo, Gimzewski, Putterman, Nature, 434, monics. Coherent high harmonic generation has been achieved with other techniques, typ- 1115). ically involving single, actively amplified, ultrashort laser pulses. The new approach demonstrated in the JILA work has drastically improved the spec- tral resolution of these high harmonic generated light sources by many orders of magni- MOST PRECISE MASS CALCULATION FOR LATTICE QCD tude and will also permit an important increase of the efficiency of the harmonic genera- A team of theoretical physicists have produced the best prediction of a particle’s mass, tion process. Moreover, the buildup of intense UV happened without the need for expen- using lattice QCD, a computational approach to understanding how quarks interact. Within sive or bulky amplifying equipment. days of their paper being submitted to Physical Review Letters, that very particle’s mass Optical frequency combs have led to demonstrations of optical atomic clocks and are was accurately measured at Fermilab, providing striking confirmation of the predicted value. furthering research in extreme nonlinear optics, precision spectroscopy, and laser pulse manip- In a lattice QCD computation, quarks are placed at the interstices of a crystal-like struc- ulation and control. Jun Ye and his colleagues believe that the new ultraviolet frequency ture. The quarks interact with each other via the exchange of gluons along the links between comb promises to provide an important tool for ultrahigh resolution spectroscopy and pre- the quarks. From this sort of framework the mass of the known hadrons can be calculated. cision measurement in that spectral domain. It will open the door to unprecedented spec- Until recently, however, the calculations were marred by a crude approximation. A big tral resolution, making it possible for scientists to study the fine structure of atoms and mol- improvement came in 2003, when uncertainties in mass predictions went from the 10% ecules with coherent XUV light. (Jones et al., Phys. Rev. Lett. 94, 193201, 2005) level to the 2% level. Progress has come from a better treatment of the light quarks and from greater computer power. The improvements provide the researchers with a realistic treatment of the “sea quarks,” the virtual quarks whose ephemeral presence has a notice- GEONEUTRINOS DETECTED able influence over the “valence” quarks that are considered the nominal constituents of a Neutrinos have very little mass and interact rarely, hadron. Now, for the first time, the mass of a hadron has been predicted with lattice QCD. but are made in large numbers inside the sun as a Andreas Kronfeld and his colleagues at Fermilab, Glasgow University, and Ohio State byproduct of fusion reactions. They are also routine- report a mass calculation for the charmed B meson Bc, consisting of an anti-bottom quark ly made in nuclear reactors and in cosmic ray show- and a charmed quark). The value they predict is 6304 +/- 20 MeV. A few days after they ers. Terrestrial detectors (usually located under- submitted their Letter for publication, the first good experimental measurement of the same ground to reduce the confusing presence of cosmic particle was announced: 6287 +/- 5 MeV. This successful confirmation is exciting because rays) have previously recorded these various kinds it bolsters confidence that lattice QCD can be used to calculate many other properties of of nu’s. hadrons. (Allison et al., Phys. Rev. Lett. 94, 172001, 2005) Now, a new era in neutrino physics has opened up with the detection of electron antineutrinos coming from radioactive decays inside the Earth. The Kamioka liquid scintillator antineutrino detector (KamLAND) PRECISE MEASUREMENT OF THE WEAK NUCLEAR FORCE in has registered the presence of candidate events of the right energy; Physicists at the SLAC accelerator have measured, with much greater precision than uncertainty in the model of the Earth’s interior makes the exact number vague, ever before, the variation in the weak nuclear force over an enormous size scale (a distance but it might be dozens of geo-nu’s. of more than ten proton diameters) for so feeble a force. Although the results were not sur- The neutrinos presumably come from the decays of U-238 or Th-232. They are prising (the weak force diminished with distance as expected) this new quantitative study sensed when they enter the experimental apparatus, where they cause a 1000-ton of the weak force helps to cement physicists’ view of the sub-nuclear world. bath of fluid to sparkle. Scientists believe the Earth is kept warm, and tectonic Physicists at SLAC extract weak effects from the much larger electromagnetic effects plates in motion, by a reservoir of energy deriving from two principal sources: involved when two electrons interact. In the case of their present experiment (E158), a pow- residual energy from the Earth’s formation and additional energy from subsequent erful electron beam scatters from electrons bound to hydrogen atoms in a stationary target. radioactive decays. The rudimentary inventory of geoneutrinos observed so far By using electrons that have been spin polarized–the weak force can be studied by look- is consistent with the theory. (Araki et al., Nature 436, 499-503 (28 July 2005) ing for subtle asymmetries in the way electrons with differing polarizations scatter from each other. One expects an intrinsic fall off in the weak force with the distance between the elec- ATOM-MOLECULE DARK STATES trons. It should also fall off owing to the cumbersome mass possessed by the Z boson. Finally, Physicists at the University of Innsbruck have demonstrated that atom pairing in the weak force weakens because the electron’s “weak charge” becomes increasingly shield- Bose-Einstein condensates (BECs) using photoassociation is coherent. Coherent pairing ed owing to a polarization of the vacuum–with virtual quarks, electrons, and W and Z bosons of atoms has been observed before using a tuned magnetic condition–a Feshbach reso- needing to be taken into account. nance–between the atoms. But molecules made that way are only feebly attached. By Previously, the weak charge has been well measured only at a fixed distance scale, a contrast the process of photoassociation–i.e. using light to fuse two atoms into one mol- small fraction of the proton’s diameter. The SLAC result over longer distances confirms ecule–allows more deeply bound molecule states to be established. The trouble is that the expected falloff. According to E158 researcher Yury Kolomensky, the result is precise the same laser light can also be absorbed to dissociate the molecules. The countermea- enough to rule out certain theories that invoke new types of interactions, at least at the ener- sure used by the Innsbruck researchers is to create a “dark state” in which the light can- gy scale of this experiment. (Anthony et al., Phys. Rev. Lett. 95, 081601, 2005) not be absorbed. A dark state is a special quantum condition: it consists of three quan- tum energy levels, two stable ground states and one excited level. If laser light at the two frequencies needed for the transitions from both the ground states to the excited state are SUPERFLUIDITY IN AN ULTRACOLD GAS OF present simultaneously, the two excitations (from the two lower energy states) can FERMION ATOMS destructively interfere with each other if there is phase coherence between the ground Superfluidity in an ultracold gas of fermion atoms has been demonstrated in an exper- states. The consequence is that no light gets absorbed and the molecules are stable. Such iment at MIT, where an array of vortices has been set in motion in a molecular Bose “electromagnetically induced transparency” has been observed before for transitions Einstein condensate (BEC) of paired lithium-6 atoms. There have been previous hints of within atoms, but the Innsbruck scientists are the first to use it for a transition between superfluidity in Li-6, but the presence of vortices observed in the new experiment clinch- a BEC of atoms and molecules. In their experiments, the same (two-color) laser light that es the case since vortices manifest the most characteristic feature of superfluidity, namely creates the dark state is also the light that photoassociates rubidium atoms into molecules. persistent frictionless flow. Johannes Hecker Denschlag says that atom-molecule dark states are a convenient tool Wolfgang Ketterle and his MIT colleagues use laser beams to hold the chilled atoms in to analyze the atom-molecule system and to optimize the conversion of atomic into place and separate laser beams to whip up the vortices. Gaseous Li-6 represents only the molecular BECs. BECs of ultracold molecules represent, because of their many internal second known superfluid among fermi atoms, the other being liquid helium-3. There are degrees of freedom (vibrational and rotational), a new field of research beyond atomic great advantages in dealing with a neutral superfluid in dilute gas form rather than in BECs. (Winkler et al., Phys. Rev. Lett. 95, 063202, 2005) APS NEWS February 2006 7

energy into directed motion like a molecular-sized ratchet. (Kwon et al. Phys. Rev. Lett. HOW EFFECTIVE WILL FLU VACCINE BE? 95, 166101, 2005) A new way of predicting the flu vaccine’s efficacy by using the tools of statistical physics was described by Michael Deem of Rice University at the APS March Meeting. To predict efficacy, researchers examine each strain’s hemagglutinin (H) protein, the major PARTICLES OF HEAT protein on the surface of influenza A virus that is recognized by the immune system. The phonon Hall effect, the acoustic equivalent of the electrical Hall effect, has been In one standard approach, researchers study all the mutations in the entire H protein from observed by physicists at the Max Planck Institut für Festkörperforschung (MPI) and the one season to the next. In another approach, researchers study the ability of antibodies pro- Centre National de la Recherche Scientifique (CNRS) in France. duced in ferrets to recognize either the vaccine strain or the mutated flu strain, which had In the electrical Hall effect, when an electrical current being driven by an electric field been thought to be a good method for predicting flu vaccine efficacy in humans. is subjected to an external magnetic field, the charge carriers will feel a force perpendicu- However, these approaches are only modestly reliable indications of the vaccine’s effi- lar to both the original current and the magnetic force, causing the electrical current to be cacy. Deem and his Rice University colleagues point out that each H protein has 5 “epi- deflected to the side. A “current” of heat can consist of free electrons carrying thermal ener- topes,” antibody-triggering regions mutating at different rates. The Rice team refers to the gy or it can consist of phonons, which are vibrations rippling through the lattice of atoms one that mutates the most as the “dominant” epitope. Drawing upon theoretical tools orig- of the sample. inally developed for nuclear and condensed-matter physics, the researchers focus on the Previously, some scientists believed that in the absence of free electrons, a magnetical- fraction of amino acids that change in the dominant epitope from one flu season to the next. ly induced deflection of heat could not be possible. The MPI-CNRS researchers felt, how- Analyzing 35 years of epidemiological efficacy data, the researchers believe that their ever, that a magnetic deflection of phonons was possible, and have demonstrated it exper- focus on epitope mutations correlates better with vaccine efficacy than do the traditional imentally in insulating samples of Terbium Gallium Garnet (a material often used for its approaches. Deem and his colleagues Vishal Gupta and Robert Earl believe that this new magneto-optical properties) where no free charges are present. The sample was held at a measure may prove useful in designing the annual flu vaccine and in interpreting vaccine temperature of 5 degrees Kelvin and was warmed at one side, creating the thermal equiv- efficacy studies. alent of an applied voltage. Application of a magnetic field of a few Tesla led to an extreme- ly small (smaller than one thousandth of a degree), yet detectable temperature difference. (Strohm et al., Phys. Rev. Lett. 95, 155901, 2005) DID YOU SAY HYDROPHOBIC WATER? Hydrophobic water sounds like an impossibility. Nevertheless, scientists at National Lab have produced and studied monolayers of water molecules (rest- HYPER-ENTANGLED PHOTON PAIRS ing on a platinum substrate) which prove to be poor templates for subsequent ice growth. Physicists at the University of Illinois at Urbana-Champaign have demonstrat- Picture the following sequence: at temperatures below 60 K, isolated water molecules will ed for the first time the entanglement of two objects not merely in one aspect of stay put when you place them on a metallic substrate. At higher temperatures, the mole- their quantum natures, such as spin, but in a multitude of ways. cules become mobile enough to begin forming into tiny islands of two-dimensional ice. In the Illinois experiment, two photons are produced in a “down-conversion” New molecules landing on the crystallites will fall off the edges into the spaces between process whereby one photon enters an optical crystal and sunders into two lesser- the islands. In this way the metal surface becomes iced over completely with a monolay- energy correlated daughter photons. The two daughter photons are entangled not er. But because the water molecules’ four bonds are now spoken for (1 to the Pt substrate just in terms of polarization, but also in a number of other ways: energy, momen- and 3 to their neighboring water molecules), the addition of more water does not result in tum, and orbital angular momentum. layer-by-layer 3D ice growth. Only when there is an amount of overlying water equivalent The photon pair can be produced in either of two crystals, and the uncertainty to about 40 or 50 layers does 3D crystalline ice completely cover the hydrophobic mono- in the production details of the individual photons is what provides the ability to layer. The PNL researchers are the first to observe this effect. For the novel hydrophobic attain entanglement in all degrees of freedom. property to show itself, the water-substrate bond has to be strong enough to form a stable Is it better to entangle two particles in ten ways or ten particles in two ways? monolayer. Weaker bonding results in a “classic” hydrophobic state, in which the water They’re probably equivalent, says Paul Kwiat, leader of the Illinois group, but for merely balls up immediately; in other words, not even a first monolayer of ice forms. the purpose of quantum computing or communication it might be of some advan- This research should be of interest to those who, for example, study the seeding of tage if multiple quantum bits (or qubits) of information can be encoded in a single clouds, where ice is nucleated on particles in the atmosphere. (Kimmel et al. Phys. Rev. pair of entangled particles. Kwiat says that his lab detects a record two million entan- Lett. 95, 166102, 2005) gled photon pairs per second with ample determination of numerous properties, allow- ing a complete characterization of the entanglement produced. (Barreiro et al, Phys. Rev. Lett. 95, 260501, 2005) THE 2005 NOBEL PRIZE IN PHYSICS The 2005 Nobel Prize in Physics was devoted to optics, with half of the prize going to Roy J. Glauber of Harvard University for his quantum theory of optical coherence, and SUPER LENSING IN THE MID-INFRARED one-quarter each going to John L. Hall (JILA, University of Colorado and National Institute Physicists at the University of Texas at Austin have made a “super lens,” a plane- of Standards and Technology, Boulder, CO) and Theodor W. Hänsch (Max Planck Institute shaped lens that can image a point source of light down to a focal spot only one- for Quantum Optics, Garching, Germany; Ludwig-Maximilians-University, Munich, eighth of a wavelength wide. This is the first time such super lensing has been Germany), for their development of ultra-high-precision measurements of light. accomplished in a functional device in the mid-infrared range of the electromag- Glauber described optical coherence and the detection of laser light in the language of netic spectrum. quantum mechanics. Glauber’s theory provided understanding of quantum “noise,” jittery Historically, lensing required a lens-shaped optical medium for bringing the and unavoidable fluctuations in the properties of light. This in turn provides information diverging rays coming from a point source into focus on the far side of the lens. on the limits of measuring light, as well on the as understanding of optical detectors that But in recent years, researchers have found that in “negative permittivity” mate- count single photons at a time. Single-photon detectors are important for applications such rials, in which a material’s response to an applied electric field is opposite that as quantum cryptography. of most normal materials, light rays can be refracted in such a way as to focus Meanwhile, Hall and Hänsch developed techniques for measuring the frequency of planar waves into nearly a point–albeit over a very truncated region, usually light to what is currently 15 digits of accuracy. These frequency-measurement techniques only a tenth or so of the wavelength of the light. helped scientists to devise fundamental definitions of physical units (for example, Hall and Such near-field optics are not suitable for such applications as reading glass- others helped to redefine one meter as the distance that light travels in 1/299,792,458 sec- es or telescopes, but have become an important technique for certain kinds of onds). Measuring optical frequency has also helped to test Einstein’s theory of special rel- nanoscale imaging of large biological molecules than can be damaged by UV ativity to record-breaking levels of precision. In addition, optical-frequency measurements light. The micron-sized Texas lens, reported in October at the Frontiers in Optics have made possible tabletop experiments that search for new physics, such as the question meeting of the Optical Society of America, consists of a silicon carbide membrane of whether the fine structure constant, the quantity that determines the inherent strength of between layers of silicon oxide. It focuses 11-micron-wavelength light, but the electromagnetic force, is changing over time. the researchers hope to push on into the near-infrared range soon. Furthermore, Hall and Hänsch are cited in particular for the recent development of the “optical fre- the lensing effect seems to be highly sensitive to the imaging wavelength and quency comb technique,” in which ultrashort pulses of light create a set of equally spaced to the lens thickness. Possible applications of the lens include direct laser frequency peaks resembling a comb. The combs can be used to measure other optical fre- nanolithography and making tiny antennas for mid-IR-wavelength free-space quencies with unprecedented precision and ease (and with much smaller equipment than telecommunications. previously possible). They enable better atomic clocks which in turn can make the Global Positioning System more precise. UNCOVERING NEW SECRETS IN A DNA HELPER The protein RecA performs some profoundly WALKING MOLECULES important functions in bacteria. Two independent A single molecule has been made to walk on two legs. papers shed light on how the bacterial protein Ludwig Bartels and his colleagues at the University of helps (1) identify and (2) replace damaged DNA California at Riverside, guided by theorist Talat Rahman while making few mistakes. Error-correction mech- of State University, created a molecule–called anisms keep DNA fidelity during replication to 9,10-dithioanthracene (DTA)–with two “feet” configured within an average of one error per billion “let- in such a way that only one foot at a time can rest on the ters” or base pairs. This research may provide substrate. insight on how damage to existing DNA from Activated by heat or the nudge of a scanning tunnel- processes such as UV radiation can be detected and ing microscope tip, DTA will pull up one foot, put down the other, and thus walk in a repaired efficiently in living organisms, including straight line across a flat surface. The planted foot not only supplies support but also keeps humans, who carry evolutionary cousins of RecA. the body of the molecule from veering or stumbling off course. When the double-helix DNA is seriously dam- In tests on a standard copper surface, such as the kind used to manufacture microchips, aged, single-stranded DNA is exposed and RecA the molecule has taken 10,000 steps without faltering. According to Bartels, possible uses polymerizes (bonds) onto it, activating a biochemical SOS signal. of an atomic-sized walker include guidance of molecular motion for molecule-based infor- To do this, Tsvi Tlusty and his colleagues at the Weizmann Institute and Rockefeller mation storage or even computation. University suggest that RecA performs “kinetic proofreading” in which RecA can precise- DTA moves along a straight line as if placed onto railroad tracks without the need to ly identify a damaged strand and its length by using ATP (the energy-delivering molecule fabricate any nano-tracks; the naturally occurring copper surface is sufficient. The in cells) to inspect (proofread) the DNA’s binding energy and to detach after a certain time researchers now aim at developing a DTA-based molecule that can convert thermal delay (the “kinetic” part) if the DNA has the “wrong” binding energy. 8 February 2006 APS NEWS

The researchers argue that the RecA performs the precise binding and unbinding actions that are necessary for kinetic proofreading through “assembly fluctuations,” a protein’s struc- LIQUID CARBON CHEMISTRY tural changes brought about by constant bonding and dissociation of RecA from its target. The chemistry of carbon atoms, with their gregarious ability to bond to four other According to the authors, this is the first known biological process in which kinetic proof- atoms, is a major determinant of life on Earth. But what happens when carbon is heated reading and assembly fluctuations are combined (Tlusty et al., Physical Review Letters, 17 up to its melting temperature of 5000 K at pressures greater than 100 bars? Although liq- December 2004, Phys. Rev. Lett. 93, 258103 (2004)). uid carbon may exist inside the planets Neptune and Uranus, the main interest in studying Meanwhile, researchers at L’Institut Curie in France (Kevin Dorfman and Jean-Louis liquid carbon here on Earth might be in the indirect information provided about bonding Viovy) have studied how RecA exchanges a damaged strand with a similar copy. in ordinary solid carbon or in hypothetical novel forms of solid carbon. A new experiment In bacteria, RecA protein catalyzes this process by binding to a healthy single DNA strand creates liquid carbon by blasting a solid sheet of carbon with an intense laser beam. Before to form a filament that “searches” for damaged double-stranded DNA (dsDNA). At odds the liquid can vaporize, its structure is quickly probed by an x-ray beam. At low carbon with the conventional view, they propose that the dsDNA which needs to be repaired is the density, two bonds seem to be the preferential way of hooking up, while at higher densi- more active partner in this mutual search. Unbound, it first diffuses towards the more rigid ty, three and four bonds are typical. and thus less mobile filament. In a second step, local fluctuations in the structure of the This is not to say that complex organic molecules (carbon bonded to other atoms such dsDNA, caused only by thermal motion, allow the base pairs of the filament to align and as hydrogen or oxygen) could survive at 5000 K, but carbon bonds are tougher and can pair with the strand of replacement DNA. (Dorfman et al, Phys. Rev. Lett. 93, 268102, 2004) persist. The experiment was performed by physicists from UC Berkeley, the Paul Scherrer Institute (PSI) in , Lawrence Berkeley National Lab, Kansas State, and Lawrence Livermore National Lab. A team member, Steve Johnson, says that one next step will be ELECTRON CLOUDS CAN FREEZE INTO AN “ORBITAL GLASS” to study carbon, as well as other materials, at even higher temperatures in order to look at Electron clouds can freeze into an “Orbital Glass” at low temperatures. In the modern “warm dense matter,” a realm of matter too hot to be considered by conventional solid- picture of quantum mechanics, electrons take the form of “clouds” within the atoms and state theory but too dense to be considered by conventional plasma theory. (Johnson et al., molecules in which they inhabit. The clouds, which have various shapes such as spheres Phys. Rev. Lett. 94, 057407, 2005) or dumbbells, represent the general boundaries within which one may find an electron at any one measurement in time. Typically, processes involving electron clouds (more for- mally known as “orbitals”) are blazingly fast. In the order of a femtosecond (10-15 s), for 240 ELECTRONS SET IN MOTION example, an electron orbital can make transitions between degenerate states (those con- A soccerball-shaped carbon-60 taining the same amount of energy), transforming from a vertical dumbbell to a horizon- molecule, possessing a mobile tal one with respect to some axis. team of up to about 240 valence Now, scientists have found evidence that these and other orbital processes can slow down electrons holding the structure dramatically–to as long as 0.1 seconds, a slowing by 14 orders of magnitude–for electrons together, is sort of halfway in low-temperature FeCr2S4, a spinel (class of mineral) with a relatively simple crystalline between being a molecule and a structure. The researchers, from the Center for Electronic Correlations and Magnetism at solid. To explore how all those the University of Augsburg in Germany (Peter Lunkenheimer) and the Academy of Sciences electrons can move as an ensem- of Moldova, consider these frozen electron orbitals in spinels to constitute a new class of ble, a team of scientists working material which they have dubbed an orbital glass. By measuring the response of the mate- at the Advanced Light Source syn- rial to alternating-current electric fields in the audio- to radio-frequency range, they found chrotron radiation lab in Berkeley, that processes involving non-spherical orbitals dramatically slow down at low temperatures turned the C-60 molecules into a to form a glass-like state, in a manner very similar to the arrest of molecular motion that beam (by first ionizing them) and occurs when glass blowers perform their craft. then shot ultraviolet photons at It’s not just the orbitals that slow down; the neighboring atomic nuclei that surround the them. When a photon is absorbed, electrons also distort more slowly in response to the glacially changing orbitals. In con- the energy can be converted into a collective movement of the electrons referred to as a trast to conventional glasses, a complete “freeze” of the electron clouds does not occur at plasmon. the lowest temperatures. Completely frozen orbitals are prevented by quantum-mechani- Previously a 20-electron-volt “surface plasmon” was observed: the absorption of the cal tunneling: the clouds keep themselves moving by making transitions between differ- UV energy resulted in a systematic oscillation of the ensemble of electrons visualized as ent low-energy cloud configurations even without the energy they normally require. (Fichtl a thin sphere of electric charge. Now a new experiment has found evidence of a second et al., Phys. Rev. Lett. 94, 027601, 2005) resonance at an energy of 40 eV. This second type of collective excitation is considered a “volume plasmon” since the shape of the collective electron ensemble is thought to be oscil- lating with respect to the center of the molecule. COMPLEX HYBRID STRUCTURES The collaboration consists of physicists from the University of , Reno, Lawrence Complex hybrid structures, part vortex ring and part soliton, have been observed in a Berkeley National Lab, Justus-Liebig-University (Giessen, Germany), and the Max Planck Bose-Einstein condensate (BEC) at the Harvard lab of Lene Vestergaard Hau. Hau pre- Institute (Dresden). (Scully et al., Phys. Rev. Lett. 94, 065503, 2005) viously pioneered the technique of slowing and then stopping a light pulse in a BEC con- sisting of a few million atoms chilled into a cigar shape about 100 microns long. In the new experiment, two such light pulses are sent into the BEC and stopped. The DEGENERATE GAS STUCK IN OPTICAL LATTICE entry of these pulses into the BEC set in motion tornado-like vortices. These swirls are Physicists at the ETH lab in Zurich have, for the first time, not only made a quantum further modulated by solitons, waves which can propagate in the condensate without los- degenerate Fermi gas but have been able to load the atoms into the criss-cross interstices ing their shape. The resultant envelope can act to isolate a tiny island of superfluid BEC of an optical lattice, an artificial 3D crystal in which atoms are held in place by the elec- from the rest of the sample. tric fields of well-aimed laser beams. The dynamic behavior of the structures can be imaged with a CCD camera by shin- By adjusting an external magnetic field, the pairs of atoms lodged in their specified sites ing a laser beam at the sample. Never seen before, these bizarre BEC excitations some- can be made to interact (courtesy of the “Feshbach resonance”) with a varying strength. times open up like an umbrella. Two of the excitations can collide and form a spherical According to Tilman Esslinger, it is this ability to put atoms where you want them in a crys- shell (the vortex rings taking up the position of constant latitudes). Two such rings, cir- tal-like scaffolding, and then to make them interact with a strength that you can control, culating in opposite directions, will co-exist for a while, but after some period of push- that makes this setup so useful. It might be possible to test various condensed matter the- ing and pulling, they can annihilate each other as if they had been a particle-antiparticle ories, such as those that strive to explain high-temperature superconductivity, on a real phys- pair. ical system. (Kohl et al., Phys. Rev. Lett. 94, 080403, 2005) Hau and her colleagues, graduate student Naomi Ginsberg and theorist Joachim Brand (at the Max Planck Institute for the Physics of Complex Systems, Dresden), have devised USING THE LHC TO STUDY HIGH ENERGY DENSITY PHYSICS? a theory to explain the strange BEC excitations and believe their new work will help physi- The Large Hadron Collider (LHC) will be the cists gain new insights into the superfluid phenomenon and into the breakdown of super- most powerful particle accelerator around conductivity. (Ginsberg, Brand, Hau, Phys. Rev. Lett. 94, 040403, 2005) when, according to the plans, it will start operating in the year 2007. Each of its two 7- EVIDENCE FOR QUANTIZED DISPLACEMENT TeV proton beams will consist of 2808 Physicists at University have found evidence for bunches and each bunch will contain about quantized displacement in nanomechanical oscillators. 100 billion protons, for a total energy of 362 They performed an experiment in which tiny silicon megajoules, enough to melt 500 kg of copper. paddles, sprouting from a central stick of silicon like the vanes What if one of these full-power beams were to from a heat sink, seem to oscillate together in a peculiar accidentally strike a solid surface, such as a beam pipe or a magnet? manner: the paddles can travel out to certain displacements To study this possibility, scientists have now simulated the material damage the beam would but not to others. The setup for this experiment consists of cause. (In the case of an actual emergency, the beam is extracted and led to a special beam dump.) a lithographically prepared structure looking like a double- The computer study showed, first of all, that the proton beam could penetrate as much as 30 m of sided comb. solid copper, the equivalent of two of LHC’s giant superconducting magnets. It is also indicated Next, a gold-film electrode is deposited on top of the that the beam penetrating through a solid material would not merely bore a hole but would create spine. Then a current is sent through the film and an exter- a potent plasma with a high density (10 percent of solid density) and low temperature (about 10 eV). nal magnetic field is applied. This sets the structure to vibrat- Such plasmas are known as strongly coupled plasmas. One way of studying such plasmas ing at frequencies as high as one gigahertz. This makes the would therefore be to deliberately send the LHC beam into a solid target to directly induce states structure the fastest man-made oscillator. At relatively warm temperatures, this rig behaves of high-energy-density (HED) in matter, without using shock compression. This is a novel according to the dictates of classical physics. The larger the driving force (set up by the technique and could be potentially a very efficient method to study this venerable subject. magnetic field and the current moving through the gold electrode) the greater the excur- (Tahir et al., Phys. Rev. Lett. 94, 135004, 2005) sion of the paddles. At millikelvin temperatures, however, quantum mechanics takes over. In principle, the NICKEL-78, THE MOST NEUTRON-RICH OF THE DOUBLY- energies of the oscillating paddles are quantized, and this in turn should show up as a propen- MAGIC NUCLEI sity of the paddles (500 nm long and 200 nm wide) to displace only by discrete amounts. Nickel-78, the most neutron-rich of the doubly-magic nuclei, has had its lifetime meas- The Boston University experiment sees signs of exactly this sort of behavior. (Gaidarzhy ured for the first time, which will help us better understand how heavy elements are made. et al., Phys. Rev. Lett. 94, 030402, 2005) APS NEWS February 2006 9

Physicists believe gold and other heavy elements (beyond iron) were built from lighter atoms through a novel approach referred to as ballistic bit addressing. inside star explosions billions of years ago. In the “r-process” (r standing for rapid) unfold- In the case of the new MRAM architecture, the influence of magnetic excitations is elim- ing inside the explosion, a succession of nuclei bulk up on the many available neutrons. inated through the use of very short (500 picosecond) current pulses for carrying out the This evolutionary buildup is nicely captured in a movie simulation showing all the species write operation. The 2-GHz switching speed (the rate at which writing can be accomplished) in the chart of the nuclides being made one after the other. In some models the buildup can is faster than static RAM (or SRAM) memories, currently the fastest memories, can accom- slow down at certain strategic bottlenecks. Nickel-78 is one such roadblock. This is because plish. Furthermore, the magnetic memories are non-volatile, which means that the status Ni-78 is a “doubly magic” nucleus. It has both closed neutron and proton shells; it is “noble” of the memory does not disappear if the computer is shut down. (Schumacher, Appl. Phys. in a nuclear sense in the way that a noble gas atom is noble in the chemical sense owing Lett. 87, 042504, 2005, J. Appl. Phys. 98, 033910, 2005) to its completely filled electron shell. This crucial nuclide is very rare and hard to make artificially. Nevertheless, scientists A NEW KIND OF NANOPHOTONIC WAVEGUIDE at the National Superconducting Cyclotron (NCSL) at Michigan State University have now A new kind of nanophotonic waveguide has been created at MIT, overcoming several culled 11 specimens of Ni-78 from among billions of high-energy collision events record- long-standing design obstacles. The device might lead to single-photon, broadband and more ed. In effect, the NCSL is a factory for reproducing supernova conditions here on Earth. compact optical transistors, switches, memories, and time-delay devices needed for opti- Hendrik Schatz, speaking at the April APS meeting in Tampa, reported that from the avail- cal computing and telecommunications. able Ni-78 decays recorded, a lifetime of 110 milliseconds could be deduced. If photonics is to keep up with electronics in the effort to produce smaller, faster, less- This is some 4 times shorter than previous theoretical estimates, meaning that the bot- power-hungry circuitry, then photon manipulation will have to be carried out over scales tleneck nucleus lived shorter than was thought, which in turn means that the obstacle to of space, time, and energy hundreds or thousands of times smaller than is possible now. making heavier elements was that much less. So far the exact conditions and site for the r- One or two of these parameters (space, time, energy) at a time have been reduced, but until process are still unknown. With the new measurement model conditions have to be read- now it has been hard to achieve all three simultaneously. John Joannopoulos and his MIT justed to produce the observed amounts of precious metals in the universe. This will pro- colleagues have succeeded in the following way. To process a photonic signal, they encrypt vide a better idea of what to look for when searching for the site of the r-process. (See also it into light waves supported on the interface between a metal substrate and a layer of insu- Hosmer et al., Phys. Rev. Lett. 94, 112501, 2005) lating material. These waves, called surface plasmons, can have a propagation wavelength much smaller than the free-space optical wavelength. This achieves one of the desired THE FIRST DIRECT MEASUREMENT OF RECOIL MOMENTUM reductions: with a shorter wavelength the spatial dimension of the device can be smaller. The first direct measurement of recoil momentum for single atoms struck by light in an Furthermore, a subwavelength plasmon is also a very slow electromagnetic wave. Such absorptive medium has been made by Gretchen Campbell, Dave Pritchard, Wolfgang a slower-moving wave spends more time “feeling” the nonlinear properties of the device Ketterle and their colleagues at MIT. Photons do not possess mass, but a beam of light does materials, and is therefore typified by a lower device-operational-energy scale, thus achiev- carry momentum. In general, when light strikes a mirror, the mirror will recoil ever so slight- ing another of the desired reductions. Finally, by stacking up several insulator layers, the ly, and this recoil has previously been measured. But what about a single photon striking slow plasmon waves occupy a surprisingly large frequency bandwidth. Since the superpo- a single atom in a dilute gas? sition of waves at a variety of frequencies can add up to a pulse that is very short in the The momentum of a photon equals h/lambda, where h is Planck’s constant and lambda time domain, the third of the desired scale reductions is thereby achieved. is the wavelength of the light in vacuum. In a dispersive medium, the index of refraction Reducing energy loss is another virtue of the MIT device. The plasmons are guided around for the medium, n, comes into play: an object absorbing the photon will recoil with a momen- on the photonic chip by corrugations on the nano-scale. In plasmonic devices the tum equal to nh/lambda. This is what has been measured for the first time on an atomic corrugations have usually been in the metal layer; this has always led to intractable prop- basis. agation losses. However, in the MIT device they reside in the insulator layer; this, it turns The MIT team used laser beams sent into a dilute gas; a beat note between recoiling out, allows for a drastic reduction of the losses by cooling. (Karalis et al., Phys. Rev. Lett. atoms and atoms at rest provided the momentum measurement of selected atoms. The fact 95, 063901, 2005) that the recoil momentum should be proportional to the index of refraction came as some- thing of a surprise to the experimenters. You might expect that in isolated encounters, when an individual atom absorbs a single photon, that the recoil of the atom should not depend ROOM-TEMPERATURE ICE IN ELECTRIC FIELDS on n. That’s because the atoms in the sample–in this case a Bose-Einstein condensate of Room-temperature ice is possible if the water molecules are submitted to a high enough Rb atoms–-is extremely dilute, so dilute that each atom essentially resides in a vacuum. electric field. Some physicists had predicted that water could be coaxed into freezing at Nevertheless, the interaction of the light with all the atoms has to be taken into account, fields around 109 V/m. The fields are thought to trigger the formation of ordered hydro- even if the specific interaction being measured, in effect, is that of single atoms. The atoms gen bonding needed for crystallization. Now, for the first time, such freezing has been observed, “sense” the presence of the others and act collectively, and the extra factor, the index of in the lab of Heon Kang at Seoul National University in Korea, at room temperature and refraction, is applicable after all. Ketterle believes that this new insight about what at a much lower field than was expected, only 106 V/m. Exploring a new freezing mech- happens when light penetrates a dispersive medium provides an important correction anism should lead to additional insights about ice formation in various natural settings, Kang for high-precision measurements using cold atoms. (Campbell et al., Phys. Rev. Lett. 94, believes. 170403, 2005) The field-assisted room-temperature freezing took place in cramped quarters: the water molecules were constrained to the essentially 2-dimensional enclosure between a gold sub- strate and the gold tip of a scanning tunneling microscope (STM). Nevertheless, the exper- LIGHT MAY ARISE FROM TINY RELATIVITY VIOLATIONS imental conditions in this case, modest electric field and narrow spatial gap, might occur Light may arise from tiny relativity violations, in nature. Fields of the size of 106 V/m, for example, are thought to exist in thunderclouds, according to a new theory. Speaking at the meet- in some tiny rock crevices, and in certain nanometer electrical devices. (Choi et al., Phys. ing of the Division of Atomic, Molecular, and Rev. Lett. 95, 085701, 2005) Optical Physics in in May, Alan Kostelecky of Indiana University described how light might exist as a result of breaking Lorentz BEC IN A CIRCULAR WAVEGUIDE symmetry. In Lorentz symmetry, the laws of physics Bose Einstein condensates (BECs), in which trapped, stay the same even when you change the orienta- chilled atoms fall into a single corporate quantum state, tion of a physical system (such as a barbell-shaped have been achieved for several elements of the period- molecule) or alter its velocity. ic table and in a variety of trap geometries. Physicists Broken Lorentz symmetry would give space- at UC Berkeley have now, for the first time, produced time a preferred direction. In its simplest form, broken Lorentz symmetry could be visu- a BEC in a ring-shaped trap about 1 millimeter across. alized as a field of vectors existing everywhere in the universe. By using an extra magnetic field, in addition to those In such a picture, objects might behave slightly differently depending upon their orien- used to maintain the atoms in the trap to start with, the tation with respect to the vectors. In a recent paper, the authors propose that the very exis- whole trap can be “tilted,” so as to accelerate the atoms tence of light is made possible through a vector field arising from broken Lorentz symme- up to velocities of about 50-150 mm/sec (or equivalent- try. In this picture, light is a shimmering of the vector field analogous to a wave blowing ly to energies of about 100 pico-electron-volts per nucle- through a field of grain. on, as compared to the TeV energies sought for particle The researchers have shown that this picture would hold in empty space as well as in the physics). After this initial “launch” phase, the atoms are allowed to drift around the ring; presence of gravity, which is often ignored in conventional theories of light. This theory is they do this not in clumps (as you would have with particles in a colliding-beam storage in contrast to the conventional view of light, which arises in a space without a preferred direc- accelerator) but in a continuously expanding stream. However, starting from the BEC tion and as a result of underlying symmetries in particles and force fields. Kostelecky says state, the atoms are more like coherent atom waves smeared out around the ring; they move that the new theory can be tested by looking for minute changes in the way light interacts ballistically and without emitting synchrotron radiation. According to Dan Stamper-Kurn, with matter as the earth rotates (and changes its orientation with respect to the putative vec- potential applications for BEC rings would become possible if parts of the circulating con- tor field). (Bluhm and Kostelecky, Physical Review D, 71, 065008, 2005) densate could be made to interfere with other parts. From such an interferometer one could devise gyroscopes or high-precision rotation sensors. Other possible realms of study include quantized circulation, fluid analogues of general relativity, and fluid analogues of SQUID NEW SPINTRONIC SPEED RECORD detectors and other superconducting devices. (Gupta et al., Phys. Rev. Lett. 95, 143201, 2005) Spintronics is the science devoted to gaining greater control over digital information pro- cessing by exploiting electron spin along with electron charge in microcircuits. One draw- back to implementing a scheme of magnetic-based memory cells for computers has been MAGNETIC BURNING the relatively slower speed of spin transistors. Hans Schumacher of the Physikalisch- A new experiment suggests that the fast flipping of the magnetic orientation of some Technische Bundesanstalt, Braunscheig, Germany, has now devised the fastest-yet mag- molecules in a solid sample resembles the propagation of a flame front through a materi- netic version of a random access memory (MRAM) cell, one that switches at a rate of 2 al being burned, and that the “magnetic burning” process can be used to study flammable GHz, as good as or better than the fastest non-magnetic semiconductor memories. substances without actually having flames present. In a chemical fire–say, the burning of The MRAM architecture is a sandwich, consisting of two magnetic layers, with a tun- the pages of a book–the flame front marks a dividing point: ahead of the front is intact unburned neling layer in between. When the magnetic layers are aligned (their spin orientation is the material, while behind the front is ash, the state of material that has been oxidized in the same) resistance in the cell is low; when they are counter-aligned resistance is high. These combustion process. Now, consider the magnetic equivalent as studied by a collaboration two conditions establish the binary 1 or 0 states. The speed of writing or reading data to of scientists from CUNY-City College, CUNY-Lehman College, the Weizmann Institute, and from the cells has, for MRAMs, been limited to cycle times of 100 MHz by magnetic and the University of . A crystal of manganese12-acetate (Mn12-ac) molecules, each excitations in the layers. This problem has been overcome, according to Hans Schumacher, with a net spin of 10 units, is quite susceptible to magnetic influence. Turning on a strong 10 February 2006 APS NEWS

external magnetic field opposed to the prevailing magnetic orientation of the crystal can All of these effects are enhanced when the atoms are very cold. Moreover, cause a sudden reversal of spins of the molecules. The reversal propagates along a front because the slow light remains tightly focused over the length of the waveguide through the crystal (which can be thought of as a stack of nanomagnets) just as a flame region, intensity remains high; it might be possible to study slowed single-photon light moves through a solid in the case of a conventional combustion. In the magnetic case, much pulses, which could enhance the chances of making an all-optical transistor. The light heat will be generated as the spins get flipped (the heat energy being equal to the differ- in this setup has been slowed to speeds as low as 1500 m/sec but much slower speeds ence in energy of the before and after spin states), but there will be no destructive burning. are expected when the atoms are chilled further. (Vengalattore and Prentiss, Phys. Rev. The “ash” consists of the molecules in their new spin state. In summary, magnetic burning Lett. 95, 243601, 2005) in molecular magnets has several of the qualities of regular burning (a flame front and com- bustion) but not the destructiveness. says that magnetic burning might QUANTUM SOLVENT offer a more controlled way of learning how to control and channel flame propagation. (Suzuki Scientists at the Ruhr-Universität Bochum in Germany et al., Phys. Rev. Lett. 95, 147201, 2005) have performed high-precision, ultracold chemical stud- ies of nitrogen oxide (NO) molecules by inserting them WHY DO WE RESIDE IN A THREE-DIMENSIONAL into droplets of liquid helium. UNIVERSE? NO, Science magazine’s “molecule of the year” for Andreas Karch (University of Washington) and Lisa Randall (Harvard) propose to 1992, is important because of its role in atmospheric explain why we live in three dimensions and not some other number. Currently, the popu- chemistry and in signal transduction in biology. A radi- lar string theory of matter holds that our universe is actually ten-dimensional, including, cal is a molecular entity (sometimes charged and some- first of all, the dimension of time, then the three “large” dimensions we perceive as “space,” times neutral) which enters into chemical reactions as a plus six more dimensions that are difficult to see, perhaps because they are hidden in some unit. To sharpen our understanding of this important way. There is reason to believe, therefore, that our common 3D space is but a portion of molecule and its reactions, it would be desirable to cool it down, the better to observe some membrane or “brane” within a much more complicated higher-dimensional reality. its complex spectra of quantum levels corresponding to various vibrational and rota- Specifically, Karch and Randall address themselves to the behavior of three-dimensional tional states. force laws, including the force of gravity. Having several dimensions rolled up is one way In the new experiment, liquid helium is shot from a cold nozzle into vacuum. The to explain why gravity is so weak. resultant balls, each containing about 3,000 atoms, are allowed to fall into a pipe where Another view, pioneered by Randall and Raman Sundrum, holds that if gravity is local- NO molecules are lurking. The NO is totally enveloped and, within its superfluid-heli- ized on a 3D defect in the larger multi-dimensional universe and if spacetime is sufficient- um cocoon at a temperature of about 0.4 Kelvin, it spins freely. The helium acts pro- ly warped, then the other spatial dimensions might be large after all. But why is our “local vides a cold environment but does not interact chemically with the NO molecules. Because gravity” apparently a 3D defect in a 10D universe? Why not a 4D defect or some other of this a high-resolution infrared spectrum of NO in fluids could be recorded for the dimensionality? first time. In the present paper, Karch and Randall show that the cosmic evolution of the 10D uni- NO has been observed before in the gas phase, but never before has such a high verse, involving a steady dilution of matter, results in spacetime being populated chiefly resolution spectrum be seen in the helium environment. (Haeften et al., Phys. Rev. Lett. by 3D and 7D branes. Several versions of string theories require the existence of 3D and 95, 215301, 2005) 7D branes; indeed, the particles that constitute matter–such as quarks and electrons–can be considered open strings with one end planted on a 3D brane and the other end planted MEASURING HIGHER-LEVEL QED on a 7D brane. (Karch and Randall, Phys. Rev. Lett. 95, 161601, 2005) A new experiment at Livermore National Lab has made the best measurement yet of a complicated correction to the simplest quantum description of how atoms NUCLEAR SEISMOLOGY behave. Livermore researchers did this by measuring the Lamb shift, a subtle shift- Physicists at the GSI lab in Darmstadt, Germany, have discovered a new excited nuclear ing of quantum energy levels, including a first measurement of “two-loop” contri- state, one in which a tide of neutrons swells away from the rest of the nucleus. Ordinarily, butions, in a plasma of highly charged uranium ions. in its unexcited state, a typical atomic nucleus consists of a number of constituent neutrons For hydrogen atoms, containing but a single electron and a proton for a nucle- and protons bobbing around inside a roughly spherical shape. However, if struck by a pro- us, the Lamb shift can be measured to an accuracy of a few parts in a million, and jectile from outside, such as a beam particle supplied by an accelerator, the nucleus can be theoretical and experimental values agree very well. One would like also to meas- set to spinning, or it might distend. In one kind of excited mode called a dipole resonance, ure the Lamb shift (and hence test basic QED precepts) for other elements. One the protons can move slightly in one direction while the neutrons go the other way. In anoth- would like also to measure separately the contribution of higher-order contribu- er type of excitation, a nucleus might consist of a stable core blob of nucleons surrounded tions to the Lamb shift. by a surplus complement of one or two neutrons, which constitute a sort of halo around In hydrogen, two-loop and other higher contributions play a very small role in the core. In the new GSI experiment, yet another nuclear mode has been observed. The the Lamb shift. Furthermore, uncertainty in the size of the proton limits any effort nuclei used, two isotopes of tin, are the most neutron-rich among the heavier nuclei that to measure two-loop effects. This is not true for a uranium atom in which nearly can be produced at this time. Sn-130 and Sn-132 are so top-heavy with neutrons that they all the electrons have been stripped away. With a much larger nucleus, the proton- are quite unstable and must be made artificially in the lab. At GSI this is done by shooting size issue is much reduced, and the electric fields holding electrons inside the a uranium beam at a beryllium target. The U-238 nuclei, agitated by the collision, eventu- atom are a million times stronger (1017 volts per meter) than in hydrogen. Thus, ally fission in flight, creating a swarm of more than 1,000 types of daughter nuclei, from QED can be tested under extreme conditions. which the desired tin isotopes can be extracted for study. The tin nuclei are excited when The Livermore physicists study uranium atoms that have been stripped of all but they pass through a secondary target, made of lead. The excited tin states later disintegrate; three electrons. These lithium-like uranium ions, held in a trap, are then carefully the debris coming out allows the researchers to reconstruct the turbulent nature of the tin observed to search for the Lamb discrepancy from simple quantum predictions as nuclei. The dipole resonance was seen, as expected, but also a new resonance: an excess to the frequencies of light emitted by the excited ions. In hydrogen atoms, the of neutrons pushing off from the core nucleus. Furthermore, the neutron resonance appears two-loop corrections constitute only a few parts per million, but in uranium at a lower excitation energy than does the dipole resonance. Team leader Hans Emling says atoms they contribute about one third of one percent of the Lamb shift. In this that there was some previous evidence for the existence for the neutron mode in work with way, the Livermore team has measured this higher-level QED term for the first lighter nuclei, but not the actual oscillation observed in the present work. (Adrich et al., time, with an accuracy of about 10 percent. (Beiersdorfer et al., Phys. Rev. Lett. Phys. Rev. Lett. 95, 132501, 2005) 95, 233003, 2005)

GUIDED SLOW LIGHT A TERA-ELECTRONVOLT GAMMA RAY ORIGINATING Guided, slow light in an ultracold IN THE MILKY WAY medium has been demonstrated by The most energetic parcels of electromagnetic radiation–Tera-electronvolt Mukund Vengalattore and Mara gamma rays–ever determined to have originated in the plane of our home galaxy Prentiss at Harvard. were observed recently by the Milagro detector, located at high mountain eleva- Slowing light pulses in a sample of tions in . The potent photons are believed to have been part of the atoms had been accomplished before debris spawned when even more energetic cosmic rays struck the matter-dense by sending light pulses into a highly dispersive medium–that is, a medium in which heart of the Milky Way. the index of refraction varies greatly with frequency. Previously, this dispersive Photons in the TeV range arrive at the Earth very rarely, not often enough to quality had come about by tailoring the internal states of the atoms in the medi- permit observation from a space-based gamma telescope. Therefore, terrestrial um. In the present Harvard experiment, by contrast, the dispersive qualities come gamma observations are usually carried out by large-area-arrays attached to the about by tailoring the external qualities of the atoms, namely their motion inside ground. an elongated magnetic trap. Milagro, operated by scientists from nine institutions, records the arrival of In the lab setup, two pump laser beams can be aimed at the atoms in the trap; energetic photons at Earth by observing the air shower of secondary particles gen- depending on the frequency and direction of the pump light, the atomic cloud (at erated when the gamma rays hit the atmosphere. These particles betray their a temperature of about 10 micro-Kelvin) can be made more or less dispersive in presence by the light (Cerenkov radiation) emitted when the particles pass through a process called recoil-induced resonance, or RIR. If now a separate probe laser a 6-million-gallon pond instrumented with photodetectors. This method of obser- beam is sent along the atom trap central axis, it can be slowed by varying degrees vation offers a rough ability to determine the direction of arrival. by adjusting the pump laser beam. Furthermore, the probe beam can be ampli- For the Milagro experiment so far, 70,000 TeV photon events from within a fied or attenuated depending on the degree of dispersiveness in the atoms. This region of the Milky Way plane were culled from an inventory of about 240 mil- process can be used as a switch for light or as a waveguide. lion TeV-level events seen so far seen from the same region. These numbers, says According to Mukund (now working at UC Berkeley), slowing light with the team member Roman Fleysher of New York University, are consistent with recoil-induced resonance approach may be a great thing for nonlinear-optics theoretical estimates for cosmic ray production. research. Normally, nonlinear effects come into play only when the light inten- And where do the cosmic rays get their 100-TeV-and-more energies? Ions in sities are quite high. But in the RIR approach, nonlinear effects arise more from the interstellar medium, perhaps near a collapsed star or an active galactic the strong interaction of the two laser beams (pump and probe) and the fact that nucleus (AGN), can get caught up by shock waves and accelerated to high ener- the slow light spends more time in the nonlinear medium (the trap full of atoms). gies. (Atkins et al., Phys. Rev. Lett. 95, 251103, 2005) APS NEWS February 2006 11

Undergrad Awards Promote Student JOB FAIRS AT APS MARCH AND APRIL MEETINGS Participation at DNP Meeting MARCH 2006 APS March Meeting Job Fair Last September about 75 under- “I had a lot of positive comments March 13–15, 2006 graduates were able to mix the pleas- about my research. One group thought Baltimore, MD ure of attending a nuclear physics it was very impressive that I could APRIL 2006 conference with the business of get the project done in one summer, APS April Meeting Job Fair hanging out on the beach in . and another thought the ideas April 23 – 24, 2006 The students were in Maui attend- behind it were very interesting,” said Photo credit: Warren Rogers Dallas, TX Daniel Passmore, a student at the ing the 2005 Division of Nuclear NSF Assistant Director Michael Don’t miss the opportunity to connect with employers and job University of , Knoxville. Physics meeting as part of the Turner (in red shirt) chats with CEU seekers from all areas of physics and physical sciences. This is Scientists at the meeting have been Conference Experience for participants at an ice cream social the perfect opportunity to reach high-level candidates who will Undergraduates (CEU). Each year very impressed with the students’ during the DNP meeting in Maui. bring skill, dedication, and energy to your organization. the CEU program brings between research, said Rogers. “They are For more information, please contact Alix Brice at (301) 209-3187 70 and 90 undergraduates to the amazed at the quality of the nuclear physics. or [email protected]. DNP meeting. The students, who undergraduate work. The students Some of the 2005 CEU students say they plan to continue to study have done research in nuclear find out that their research is ENDOWED LECTURES CONTINUED FROM PAGE 1 physics, present their work at a spe- truly valued. I think that is very nuclear physics, while others have cial undergraduate poster session. motivational for them.” interests in different fields. They International Linear Collider and tered by CISA. Each year, CISA CEU draws applications from “Numerous DNPcolleagues have were certainly glad to have had the of international collaboration on will invite the APS Divisions, students around the country. These also expressed sincere appreciation chance to attend the meeting. big scientific projects. He cur- Topical Groups, and Forums to applications are reviewed by a com- for the energy and enthusiasm the “I can't believe what wonderful rently serves as the internation- submit nominations of candidates mittee, and about half receive travel students bring to the meeting, and opportunities physics has opened up al representative on the APS for the lectureships. An and lodging awards. Funding for the several have reported that meeting for me,” said Mahmood. Council. He will give a plenary announcement of the call for CEU awards is provided by the NSF the students and attending the Beverly Lau, a CEU participant talk at the April Meeting on 2007 online nominations will and DOE. Even those students who CEU poster session is for them one of from Reed College said, “If becom- “Physics Prospects and appear soon. don’t receive awards are often able the highlights of the meeting,” said ing a nuclear physicist means a free International Aspects of ILC.” “This is an outstanding to attend, with help from their advi- Rogers. trip to Maui once every five years Wagner was nominated for the opportunity for the units and sors. For many of the students, the Rogers began running the CEU –count me in!” Beller Lectureship by the CISA to work together ,” said DNP meeting is the first profession- program in 1998 after he noticed that Rogers would like to encourage Division of Particles and Beams Amy Flatten, APS Director of al conference they attend, and their few undergraduates attended the other APS units will try something and the Division of Particles and International Affairs. first time presenting their research. DNP meetings. Many undergrads similar to CEU. “Some APS units do Fields. “International activities cut across In September 2005 the DNP had participated in research at their have some undergrad involvement, Awarded occasionally in all aspects of the Society, and meeting was held in Maui as a joint universities or during a summer pro- but nothing on this scale,” said Rogers. recent years, the Beller and CISA is eager to collaborate with meeting with the Japanese Physical gram, but hadn’t had the chance to “I’ve hoped that other divisions Marshak Lectureships will now all APS units to award these Society [see APS News, January present their work at a professional would become interested in doing become annual events adminis- annual lectureships.” 2005]. In addition to the American conference. Rogers also wanted to something like this. The success (of students, 16 Japanese students encourage greater retention of CEU) within the nuclear physics INSIDE THE BELTWAY CONTINUED FROM PAGE 2 attended. There was a good exchange talented undergrads in the field of community can’t be overstated.” secondary science education and, It will require more than a robust between American and Japanese for the last twenty years, a shrink- presidential research budget request students, said CEU organizer Warren UC CONTINUED FROM PAGE 1 ing federal commitment to physical or an Energy Secretary who has Rogers of Westmont College. “It Many Los Alamos employees changes in the way the lab is run, and science research. Without the fount made science his number one pri- was really a historic opportunity.” were generally pleased that UC won he hopes that the next couple of of discoveries that basic research ority, with at least some of the dol- CEU is more than just getting the the contract, though not overly opti- years will be relatively quiet at the produces, American innovation lars to back up his rhetoric. It will students to present their research, mistic, said Holian. Morale has been lab, with no major upheavals. Keinig soon will be just a chapter in require presidential fortitude and said Rogers. Each year the CEU extremely low at LANL recently, he said he expects there will be some American history books. jawboning. The reason is plain. includes several activities especially said. chaos while restructuring takes place. Don’t get me wrong: we haven’t Conservatives in Congress will for undergrads, including two Rhon Keinig, who retired Some Los Alamos scientists worry quite lost the battle. But just because press hard for more tax cuts and special nuclear physics seminars pre- recently after 25 years at Los Alamos that emphasis at the lab may now shift we haven’t fallen flat on our faces reductions in spending. And unless sented at an advanced undergraduate said, “The people in upper manage- away from science, towards weapons yet, doesn’t mean we aren’t about the Administration makes science level. Other events for the students ment were totally incompetent. I engineering and manufacturing. “I to get our bottoms booted. Check and competitiveness a central theme included a reception, an ice cream thought people were really destroying believe there will be increasing empha- out the R&D benchmarks of the for Fiscal Year 2007, the coming social, and a graduate school informa- the science base of the laboratory.” sis on plutonium pit manufacturing United States and of our competi- months will seem like an agonizing tion session, at which representatives The new director at Los Alamos rather than scientific things,” said tors. They’re more than a little scary, slo-mo replay of the Fiscal Year from several universities and labora- will be Michael Anastasio, who is the Holian. He and Keinig both said they at least if you worry about your 2006 disaster, when appropriators, tories met with the students to dis- current director of Lawrence believe good science will continue to children’s future. usually sympathetic to science, cuss graduate school opportunities. Livermore National Laboratory. “I’ve be done in some divisions of the lab. Sadly that message hasn’t yet fumed that they had finally had The students are full participants heard good things about the new direc- The lab could perform very resonated with the macho culture of their fill of trying to clean up the in the meeting, and are encouraged to tor,” said Holian. “People seem to like necessary science if it focuses more the current administration. It’s one mess the White House was attend as many of the regular him at Livermore.” on energy problems, said Holian. “We thing if the messengers were only continuing to create. sessions as they can. Lawrence Livermore Lab will seek are an energy lab. It might be time to liberal academics who still sport Add to this the dynamics of a “I felt like I could go to any talk I a new director. Livermore is current- focus on energy problems,” he said. “Kerry for President” bumper stick- hard-fought election year, in which wanted, and felt privileged to have ly managed by the University of “The lab can do a great deal of serv- ers on their Volvos. But when they partisan politics will play a domi- that opportunity to be in the compa- California, but the contract expires in ice to the country.” are some of the titans of corporate nant role, and science could vanish ny of great research scientists,” 2007, and the DOE is planning to put “Nuclear weapons is not a growth America–the likes of Norm from the agenda of both parties, said Fatima Mahmood, a CEU that management contract out to a industry. (At least I hope not),” said Augustine, retired Chairman and unless advocates weigh in heavily. participant from Union College. “I competitive bid. Keinig. “I hope they find a better bal- CEO of Lockheed-Martin; Craig One third of the Senate seats and did attend several talks in the There has been a lot of anxiety at ance in the programmatic work. Barrett, Chairman of the Board of all of the House seats are up for regular program. I enjoyed hearing Los Alamos recently about the new Without the nuclear program, Los Intel; Ron Sugar, CEO of Northrup- grabs. And Democrats, savoring the about modern research in nuclear contractor. Los Alamos employees Alamos would not exist. But that Grumman; Lee Raymond, allegations of illegal, unethical or physics, and even when I couldn't are waiting for more detailed infor- doesn’t mean that that should Chairman of the Board and CEO of simply improper behavior that have understand a lot of the talks, I was mation on how the new management define the lab. A better balance Exxon Mobil–you’d think the racked the Republican leadership, glad to find certain terms and ideas will operate, what changes will be between weapons work, pure President would instantly pick up sense the possibility of reclaiming were familiar to me through my made, and how new pension and ben- science, and threat reduction needs the phone and invite them in. He control of Congress in November. own experience in research and from efits plans will work. Holian says he to be emplaced at LANLfor it to again might have wanted to, but for the Without a doubt, nastiness and neg- my studies in college.” does not expect very significant become a true national treasure.” better part of a year his gatekeep- ativism will dominate the campaign. Several 2005 CEU students said ers didn’t. But as the public inevitably tires that the opportunity to present their FEMALE FRIENDLY CONTINUED FROM PAGE 4 Finally, in December, heavy hit- of partisan bashing, a window of work in the poster session was the at 107 graduate institutions. Some about instituting family leave/family ters in the Administration–only one opportunity will open for science: most valuable part of the meeting. give very little information, some health insurance policies to peruse notch below the President and it could become a compelling issue “People were interested and asked give much more. Neither APS nor the database for information about including his closest advisors that both sides feature as a positive interesting questions, so that was CSWP assumes any responsibility the policies of other institutions. –opened their doors. They might counterpart to the dark sides of their good,” said Andrew Ratkiewicz of for the accuracy or the timeliness of Finally, any department chairs who not have liked what they heard, but campaigns. If that happens, the Indiana University at South Bend. the information presented. Still, this wish to add their departments (or they listened. Give them credit for nation would benefit enormously. “It was very interesting and help- should be a valuable tool for prospec- change their existing entry), should that. Time will tell whether they The House Democrats have ful to have other physicists looking tive students. contact me at [email protected] and will give their boss the bad news and embraced the innovation theme. at my work and ask me new The results can be found I’ll supply the URLfor entering data. begin to correct two decades of It’s time for the Republicans to questions. It definitely inspired me at http://cswp.catlla.com/results.php Marc Sher is Professor of “bipartisan lack of vision,” as take up the challenge. It wouldn’t to further research these unexpected The CSWP urges all readers to Physics and Director of Graduate , Nobel Laureate and hurt for them to hear from some of questions,” said Laura Stiles of the inform their seniors about this web- Admissions, College of William former SLAC Director, is fond of their constituents, and the sooner University of Kansas. site, and also urges those thinking and Mary describing the budgetary shambles. the better. 12 February 2006 APS NEWS The Back Page Changing the Climate… of Public Opinion By Spencer Weart

took this photo last August, as believed that any self-appointed ernments now take this a tourist on Baffin Island in the group of scientists would issue seriously. After all, as IArctic. Looking down the gla- alarmist, hyper-environmentalist some say, “How can sci- cier, the nearby ridge of rubble is a statements. They forestalled that by entists predict the cli- moraine, most likely dropped since promoting a complex international mate a century ahead the late 19th century. The glacier is advisory structure, led by people when they can’t predict continuing to melt back, like many appointed by governments rather weather a year ahead?” around the world. Our group also than by the scientific community. To The short answer is saw less pack ice than expected, further impede any statements that that the problems are dif- and the bird-watchers were disap- might push toward government reg- ferent, since a season’s pointed when they couldn’t check ulation, the advisory group’s conclu- climate is the average of off some high-latitude species. Such sions would have to be consensual all the season’s weather. experiences are now often in the –the unanimous findings of repre- Computers can predict news. Physicists may find their stu- sentatives of all the world’s gov- the weather a couple of dents or nonscientific friends ask- ernments. The result is the days ahead pretty well, if ing questions–or you could raise Intergovernmental Panel on Climate far from perfectly, and the issue yourself. People wonder, Change (IPCC). Surprisingly, the predicting climate a cen- is global warming really a prob- process produced useful advice. tury ahead is at about the lem? How do we know? Can we do Relentlessly confronted with the same stage. anything about it? Is it urgent? evidence and arguments of their A longer answer Photo credit: Spencer Weart One way to answer such ques- colleagues, even the science repre- would start by noting Photo of glacier on Baffin Island tions would be to invoke the author- sentatives of oil-rich states eventu- what an impressive achievement it of the parameter sets, however, get and therefore it’s urgent. Come ity of science. Many people are not ally agreed that the world is very is that computers can make models climates that group near the results again? Well, if you don’t know aware that the scientific communi- likely warming at an unprecedent- that look much like Earth’s actual from single runs of the most whether your house is on fire, but ty has finally reached a consensus ed rate, and that the most likely climate. It’s a hugely complicated advanced models, showing a warm- there’s a good chance it might be, on the risk of climate change. Public cause is the buildup of greenhouse system, but models get the winds ing somewhere in the range 1-5oC. that’s urgent. Even if there’s only a awareness has been held back by a gases due to human activities. and sea currents and rain and snow That confirms what modelers have small chance that it will ever catch belief that acknowledging the risk The key here is a simple matter: in all the right places. More impres- found ever since the 1970s: if you fire, you’re willing to spend a sig- would lead to government regula- in such a complex issue we cannot sive still, the models can track all can make any kind of model that nificant fraction of your wealth on tion, and thus the question became have certainty, and we don’t claim this through the seasons, as if the gets the past climate roughly right, insurance. For climate, one mech- politicized. Weird but true: if some- it. The scientific community, as rep- same model worked for two radical- it takes serious fudging to get it not anism that suggests we are at urgent one holds strong opinions about the resented by the IPCC, plus many of ly different planets: Summer and to warm up when you add green- risk can be explained to almost any- role of government, you can usual- the world’s leading science acade- Winter. But perhaps the most house gases. (For explanations and one able to grasp elementary ly guess from those opinions what mies and societies, only says that impressive is the natural experi- updates on many other questions physics. As cold regions grow they think about plain scientific serious global warming is more like- ment conducted in 1991. That was see http://www.RealClimate.org.) warmer, the bright snow and ice assertions on climate change. A pub- ly than not. After all, hardly anything when the volcano Pinatubo blew a But is there anything we can do? cover that reflect sunlight back into lic relations campaign, amply fund- that relates to economic or social cloud the size of Iowa into the strat- Here we are impeded by a view- space are retreating earlier in the ed by fossil-fuel corporations and policy is certain. The evidence that osphere. A relatively simple model point, supported by interests that spring, exposing dark soil and open their allies, has deliberately fos- we face a serious climate risk is predicted in advance the temporary are afraid to change their business water, which absorb sunlight, which tered doubt. The industrial coali- now stronger than the kind of evi- global cooling this would produce. models or their political models, leads to further warming, and so tion publicized the opinions of a dence we normally use in deciding Current models are even better at which insists that it is impossible to on. That’s why global warming is few people who cherry-picked items tax policy, investments in costly reproducing the event’s conse- reverse the rise of greenhouse gases showing up first in the Arctic: an from larger data sets to build unsci- highways, and the like. quences. without wrecking our economy. Yet effect scientists have predicted since entific counter-arguments. (For such How do we know the whole The modelers can get these any physicist can see that people the 19th century. You might also biased selection see Michael world is really warming up? One results only by adjusting a lot of can take many steps that actually mention a second risk, recognized Crichton’s latest thriller, State of quick and vivid answer is the parameters that are poorly known, save them money and benefit the more recently. The world’s vast Fear.) Meanwhile a few respectable unprecedented melting back of gla- such as the numbers in the model overall economy. For instance, we expanses of frozen tundra store fos- scientists took on the role, appropri- ciers, exposing archeological finds that tell how clouds are formed. can use more efficient light bulbs. sil carbon, and as the permafrost ate in science, of playing devil’s like the Alpine “iceman” that had What if they’re unconsciously Beyond that are collective actions melts, methane bubbles out; advocate–raising counter-arguments been frozen for thousands of years. fudged, or just wrong? The short- that will be beneficial in many ways, methane is an even more potent that spurred their colleagues to more The atmospheric temperature fluc- est answer is yes, they might be such as reducing the inefficiencies greenhouse gas than carbon dioxide, rigorous studies (which dismissed tuates hour by hour, so it seems a wrong. If they’re wrong one way, in cars that not only add to global and leads to further warming. the objections). The bickering over monumental task to arrive at an we might have no serious change. warming but make many countries Geoscientists have identified sever- details allowed the American media average global temperature and say But if they’re wrong the other way, spend huge sums to get foreign oil. al other mechanisms that might pos- to offer a supposedly “evenhanded” it has gotten a few tenths of a degree we will have catastrophic climate For a start, why not stop subsidiz- sibly push the climate abruptly into view, in which any scientist explain- warmer. It has indeed been a mon- change. Amidst this uncertainty we ing global warming? Currently tens a dangerous state. Possibly we are ing the risk of warming was “bal- umental task, the work of thousands can only say, again, that a damag- of billions of taxpayer dollars are approaching a tipping point. anced” by one of the few skeptics. of scientists. Most of the heat ener- ing change is more likely than not. wasted in open and hidden subsidies We can probably arrest the Half a century ago, nearly all gy added by the greenhouse effect If pressed for a more complete of fossil fuel industries and other process before it becomes irre- scientists thought greenhouse warm- isn’t stored in the wispy and incon- answer, I would tell about the study contributors to greenhouse emis- versible. The cost may be no worse ing was scarcely likely to be a prob- stant atmosphere anyway. It main- so big it needs more computer sions. (Many groups are working on than we spend on other kinds of lem. It took decades of accumulat- ly winds up in the oceans. The heat power than any group commands. this; one starting point is the Pew insurance. But not if we keep put- ing evidence, with many hard- energy seeps down gradually So it uses distributed computing. Center for Climate Change, ting off effective action. Every sci- fought debates, to convince them through the seawater, a very poor Your PC can join the effort in its idle http://www.pewclimate.org/.) entist has a public responsibility to they were wrong. Panels of scien- conductor, or is carried down by time: go to http://Climate What we need is a change in the be well enough informed about cli- tists convened on climate change slow-moving currents. The latest Prediction.net. You’ll get a set of climate–of opinion. Americans in mate change to answer the ques- hundreds of times in many coun- analysis of the temperature structure parameters for a simplified model, particular ought to make their nation tions that we may be asked. And tries. As scientists, most of the pan- in all the main ocean basins shows and run it to see if it will reproduce not the world’s laggard, but its we all have a responsibility to elists were professional skeptics. a strong and rapid warming in recent the 20th century’s climate (one of my leader in addressing the problem. engage in the effort to change the Yet since the late 1970s essentially decades. Moreover, the geograph- runs ended up with no clouds, other We should be challenging other climate of opinion, and quickly, on every such panel has concluded that ic and depth patterns closely match people had all the water precipitate nations to match us in staving off what might be the most crucial issue warming could become a bad prob- the predictions that computer mod- as ice at the poles, etc.). Once you global warming. Many tools are of our times. Just possibly might. lem someday. In the present centu- els make for greenhouse gas warm- get a set of parameters that gives a already at hand and many more can Actually, more likely than not. ry, every respectable panel has con- ing. The patterns cannot be matched fair approximation to the known be developed. If the climate does Spencer Weart is director of the cluded that it probably will be a to any other cause, such as variations past climate, you can double the turn bad, we may have to use most Center for History of Physics at the severe problem, and soon. in the Sun. carbon dioxide in the atmosphere of them. The necessary large change American Institute of Physics. Some people suspect such pan- How do we know the computer and run it again. The results from in public attitudes is certainly pos- Further Reading: els are just an old-boy-and-girl net- models are any good? Never before thousands of runs with different sible, for leaders of many corpora- Weart, Spencer R., 2003. The work looking out for its own in human history have nations been parameter sets are revealing. A few tions, state and local governments, Discovery of Global Warming. research funds. History helps count- asked to stake major policies on sets of parameters give no warming. and others have noticed the danger Cambridge, MA: Harvard er that suspicion, for the origins of such complex scientific calcula- A larger number of sets produces and are starting to take action on University Press; more extensive the present consensus are reveal- tions. I find it a hopeful sign, a big shockingly large warming, up to their own. and updated text at http://www.aip. ing. The Reagan administration advance in rationality, that all gov- 11oC by the end of the century. Most How urgent is it? We don’t know, org/history/climate.

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