What will this year's winner of the Nobel Prize in physics be doing when the Swedish Academy of Sciences makes its decision in October? When the call comes from Stockholm (winners from the United States usually are notified in the early hours of the morning), will the laureate be sound asleep, dreaming about superstrings or superconductivity? Or will he or she be wide awake, pondering the next equation, the newest experiment?
When Alfred Nobel wrote his will in November 1895, he established what many consider to be the most prestigious of all awards. Yet actual guidelines set down in the will for the Nobel Prize are, for the most part, sparse. The prizes were to go "to those who, during the preceding year, shall have conferred the greatest benefit on mankind." For the field of physics, in particular, Nobel directed that the award go to the person "who shall have made the most important discovery or invention within the field."
Judging which of the many extraordinary advances in the highly varied field of physics is the most important undoubtedly is no easy task. Previous Nobel Prizes in physics, for example, have been awarded for high-temperature superconductors, energy production in stars, nuclear shell structures, and scanning tunneling microscopy. Last year's winners (The Scientist, Nov. 13, 1989, page 18) were cited for their work on the separated field method (Norman F. Ramsey) and the ion trap technique (Hans G. Dehmelt and Wolfgang Paul).
In the past years, many prolific researchers have contributed much to the understanding of the physical properties of the universe; those who are given to trying to predict the Nobel committee's choices may have a hard time coming up with a list of candidates.
Polling prominent scientists and asking them their choices for Nobel candidates is one way to compile such a list. Another way is to analyze a list of previous Nobel winners, searching for any similarities among this year's crop of contenders.
Determining the impact of a physicist's work is still another way to select possible contenders and one way to determine that impact is by reviewing his or her citation record. Last year, The Scientist compiled a list of 20 Nobel "nominees" in physiology or medicine based on their citation data and past awards (The Scientist, Oct. 2, 1989, page 14). Two scientists on that list--J. Michael Bishop and Harold E. Varmus--did go on to receive the 1989 Nobel Prize in physiology or medicine.
Will the same method of reviewing citation records and past awards prove an accurate predictor of the 1990 Nobel laureate in Physics? The Scientist reviewed the 1,000 most cited scientists for the period 1973 to 1984, as tabulated by the Institute for Scientific Information in Philadelphia. Physicists appearing on the list were extracted, their past achievements were investigated, and their citation data for the period 1981 to 1988 were tallied. Based on this information, The Scientist has put together a list of likely candidates for the Nobel Prize in Physics. Although the list is predominantly composed of American scientists or those affiliated with American institutions, one should keep in mind that the Nobel Prize is an international award. The predominance of American physicists could be a function of the type of journals (largely those published in the United States) indexed by the Institute for Scientific Information.
If the Nobel committee chooses once again to honor physicists for their work in conductivity, then Marvin L. Cohen, 55, of the University of California, Berkeley, certainly has to be a candidate. Cohen perhaps is best known for his work on band structures of semiconductors. His most cited paper to date deals with band structures and pseudopotential form factors of diamond and zinc-blend semiconductors (Physical Review, 141:789-96, 1966).
Cohen, who received his doctorate in theoretical solid state physics from the University of Chicago, continues his research in this area, as well as in superconductors, semiconductors, electric properties of solids, and surface properties of solids. Throughout his career, he has received a number of fellowships and awards, including Alfred P. Sloan and Guggenheim fellowships, a U.S. Department of Energy award, and the Oliver E. Buckley Prize for Solid State Physics from the American Physical Society. He is currently a fellow of the American Physical Society as well as a member of the National Academy of Sciences. He is the 110th most cited scientist for the period 1973-84, and he is among the top 0.02 percent of cited researchers for 1981-88.
Another very highly cited researcher in superconductive properties is Alan J. Heeger, currently with the department of physics at the University of California, Santa Barbara. Heeger, 54, is the 64th most cited scientist during the period 1973-88, with well over 8,000 total citations to his works. He also has a healthy citation record for the period 1981-88. Heeger, who received his doctorate in physics from the University of California, specializes in the fundamental physical properties of synthetic materials and the superconductive properties of one-dimensional solids. One of his most highly cited articles (L.B. Coleman, et al., Solid State Communications, 12:1125-32, 1973) deals with superconducting fluctuations in a class of organic charge transfer salts.
In the past, the Nobel committee has honored researchers for their work on various forms of spectroscopy. In 1981, Arthur L. Schawlow of Stanford University and Nicolaas Bloembergen of Harvard University won it for their work on laser spectroscopy, and Kai M. Siegbahn of Uppsala University, Sweden, for his contribution to high-resolution electron spectroscopy. If the committee chooses to honor this area of endeavor again, William E. Spicer, of Stanford University definitely is a contender. Spicer ranked 225th in total number of citations during 1973-84 and is among the top 0.1 percent of cited researchers for 1981-88. Spicer has worked extensively on photoelectric emission studies of various metals and metal alloys and on surface properties of materials. He has contributed to well over 300 papers, of which more than two dozen have been cited at least 50 times each. Among his most cited papers is one he cowrote with then-graduate student Carl N. Berglund. This paper ("Photoemission studies of copper and silver: theory," Physical Review, 136:1030A-64A, 1964) presented methods researchers can use to interpret photoemission data in terms of band structure, optical excitation probabilities, and scattering probabilities.
Should the Nobel committee choose to honor work done in particle physics, John Ellis of the Organization Europeenne pour la Recherche Nucleaire (CERN) in Geneva, Switzerland, has to be taken seriously as a contender for the 1990 physics prize. Ellis, who ranks 343th among the most cited scientists during the period 1973-84, also is among the top 0.02 percent of cited scientists for 1981-88. One of his most-cited works is a paper written in 1977 with several other scientists (including Mary K. Gaillard and D.V. Nanopoulos) at CERN on the phenomenology of the left-handed quarks (Nuclear Physics B, 131:285-307, 1977). During the past 15 years, he has also contributed to a wealth of papers on supergravity and supersymmetry and their role in grand unified theories. Gaillard, who is currently at the University of California, Berkeley, and the Lawrence Berkeley Laboratory, herself ranks high. Her research interests include elementary particle theory, unification of fundamental interactions, supercollider physics, and effective theories of particle physics based on superstring theories. She was the 394th most cited scientist during 1973-84. Nanopoulus, who is among the top 0.02 percent of cited researchers during the last decade, still collaborates with Ellis at CERN.
Phase transition theory--a field important to materials scientists, ceramicists, physicists, and geologists--has been honored by the Nobel committee in the past. Michael E. Fisher, 59, currently at the University of Maryland, College Park, is perhaps best known for his pivotal work on equilibrium statistical mechanics of phase transitions and critical phenomena. Developments based on his classic paper on the theory of equilibrium critical phenomena (Rep. Progr. Phys., 30:615-730, 1967), later influenced Kenneth G. Wilson's Nobel Prize-winning work on the renormalization group technique.
Wilson, 54, who currently teaches at Ohio State University in Columbus, worked with Fisher while both men were at Cornell University in Ithaca, N.Y. Although Fisher doesn't rank among the top 500 most cited scientists in either 1973-84 or 1981-88, he has won a number of awards for his work on phase transitions. These awards include the Irving Langmuir Prize in Chemical Physics (1971), the Michelson-Morley Award (1982), and the Wolf Foundation (of Israel) Prize for Physics (1980). It is interesting to note that physicists Subrahamanyan Chandrasekhar and Louis A. Alvarez, who both won Case Western Reserve University's Michelson-Morley Award, later received the Nobel Prize. The same can be said for the Wolf Foundation Prize: both Kenneth G. Wilson and Leon Lederman received this prize prior to winning the Nobel Prize.
Should the Nobel committee members cast their eyes toward Princeton, N.J., they would find a number of physicists from which to choose--that is, if the committee would consider giving the prize to theoretical physicists as opposed to experimental physicists. One such theoretician is David J. Gross, 49, Eugene Higgins Professor of Physics at Princeton University. Gross, who ranks 310th among the most cited scientists of 1973-84, received a fellowship from the MacArthur Foundation in 1987 and the J.J. Sakurai Prize from the American Physical Society in 1986. A member of the National Academy of Sciences, he has co-written a number of highly cited articles. Perhaps his most notable papers are those he wrote with Jeffrey A. Harvey, Emil Martinec, and Ryan Rohm. These papers (Phys. Rev. Lett., 54:502-5, 1985, and Nucl. Phys. B, 256:253-84, 1985) introduced and then detailed a new type of superstring unified field theory.
Although the superstring theory papers are Gross's most popular endeavor, his most cited papers are two articles he cowrote with Frank A. Wilczek. These two papers pertain to asymptotically free gauge unification theories (Phys. Rev. Lett., 30:1343-46, 1973; Phys. Rev. D, 8:3633-52, 1973). Wilczek, 39, who is a professor at the Institute for Advanced Study in Princeton (and a regular contributor to The Scientist's "Articles Alert" column), was the 605th most cited scientist for the period 1973-84, and he falls within the top 0.3 percent of cited scientists for 1981-88. He shared the J.J. Sakurai Prize with Gross in 1986. He was also a MacArthur Foundation Fellow from 1982 to 1987, and is a member of the National Academy of Sciences. A prolific author (he has produced more than 150 papers over the past 17 years), he has contributed to a number of areas in theoretical physics, including string theory, particle physics, and gauge theories.
If the prize is awarded for work on the string theory, the prize could very well be shared by Michael B. Green of Queen Mary College in London, John H. Schwarz of the California Institute of Technology in Pasadena, and Edward Witten of Princeton. Green and Schwarz are often credited with being the rekindling force behind string theory. Two of their influential (and highly cited) papers appeared in the mid-1980s ("Anomaly cancellations in supersymmetric D = 10 gauge theory and superstring theory," Physics Letters B, 149:117-22, 1984; and "Infinity cancellations in SO(32) superstring theory," Physics Letters B, 151:21-5, 1985). At 39, Witten, who is the leading proponent of the superstring theory of unification, has the distinction of being the most-cited physicist of the past decade. In fact, he ranks 19th in terms of total citations for the period 1981-88. Witten also recently made The Scientist's list of most-cited researchers under the age of 45 (The Scientist, May 28, 1990, page 18). To date, he has written more than 40 papers that have collected at least 50 citations each.
These papers cover a number of topics, including superstrings, neutrino masses, and the relationship between physics and mathematics. In addition to his impressive citation history, Witten has also received a number of notable awards, including the Einstein Medal from the Einstein Society of Berne, Switzerland (1982); the Award for Physical and Mathematical Sciences from the New York Academy of Physics (1985); the Dirac Medal for his contributions to quantum field theory from the International Center for Theoretical Physics, Italy (1985); and the Alan T. Waterman Award from the National Science Foundation (1986) for his contributions to elementary particle physics and the unification theory.
Will one of the researchers named in this list of worthy candidates for the 1990 Nobel Prize in physics actually receive the call from Sweden? Come mid-October, all the world will know.