ITHACA, N.Y. -- James W. York, a professor of physics at Cornell University who theorizes about universal time, space and gravity, has been awarded the prestigious Dannie Heineman Prize for Mathematical Physics by the American Physical Society and the American Institute of Physics. The prize is regarded as one of the world's major scientific awards, and at least six Nobel prize winners are among previous recipients.

York, a theorist in the rarified field of mathematical physics, shares the prize with Yvonne Choquet-Bruhat of the Faculté des Sciences de Paris, who in 1979 became the first woman elected to the 300-year-old French Academy of Sciences. The value of the prize is $7,500.

The prize was awarded for the two scientists' separate and joint work in proving the existence of solutions to Einstein's gravitational field equations. "The new form of the equations was required to be practical from the point of view of developing computer simulations," says York. "The original form of the equations was unwieldy in this respect and no one had been able to carry out even the first step of such a program for many decades."

York came to the Cornell campus in January from the University of North Carolina (UNC) at Chapel Hill, where he had been Inter-Institutional Distinguished Professor of Physics, since 2001, and the Agnew Hunter Bahnson Jr. Distinguished Professor of Physics, since 1989. He first joined the UNC faculty in 1973 as an associate professor. He has been an assistant professor at North Carolina State University (NCSU) and a lecturer and assistant professor at Princeton University. He also has been a visiting professor at the Université de Paris VI, the University of Texas and the University of Maryland. He obtained his B.S. in 1962 and his Ph.D. in 1966, both at NCSU.

York's research over the years has been in the areas of general relativity, gravitation and the extension of statistical mechanics to relativistic gravitation and quantum gravitation. But, he says, the work for which he was awarded the Heineman Prize "was the result of my decision, some 33 years ago, to develop mathematically elegant and faithful reformulations of Einstein's field equations -- which describe gravity as curved space-time geometry -- that would more clearly reveal their content." York's goal was to spur development of highly complex computer models, or simulations, of the problems, and this, in turn, demanded a "practical" reformulation of the Einsteinian equations. This, York and Choquet-Bruhat succeeded in doing with four of the 10 Einstein equations that deal with possible "snapshots" of curved space at any one time.

Current work on this problem deals with how curved, three-dimensional spaces evolve and change over time. This work brings in the remaining six gravity equations. "Such a grand undertaking would be to describe clearly how to set up a problem on the scale of a galaxy with an active nucleus," says York.

He notes that the "hottest problem" in the field at present is to make computer simulations of astrophysical, distant, "strong" sources of gravity waves. "An exciting example, very difficult to compute," he observes, "is the output of what may be a tornado-like infall and collision of two orbiting black holes as their orbit decays. Such waves on a much weaker scale have been indirectly detected by observations of the decaying orbits of a pulsar (a fast-rotating neutron star) in a binary orbit with another neutron star."

Working at Cornell's Laboratory for Elementary Particle Physics and Center for Radiophysics and Space Research, York is "now shooting for larger, more challenging prey than anyone has bagged so far: developing the understanding and implementation of Einstein's equations even further."

York is a fellow of the American Physical Society (1990) and has published more than 100 research articles in major journals. He is co-editor of The Complete Works of Cornelius Lanczos (NCSU, Raleigh, 1997) and, in 1973, helped organize, at Princeton, the first international meeting to discuss the first discovery of a pulsar in the Crab Nebula. He and Choquet-Bruhat are now writing a book describing their understanding of Einstein's theory.

The Heineman Prize was established in 1959 and is awarded solely for valuable published contributions made in the field of mathematical physics. It honors Dannie Heineman, the late engineer, business executive and philanthropic sponsor of the sciences.