Wilson’s pioneering work in nuclear astrophysics, in particular, his models of supernovae core-collapse, neutrino transport, shock-propagation and magnetically driven jets, essentially launched the field of numerical relativity.
James Ricker Wilson died on Tuesday, August 14th, 2007.
Wilson was born October 21, 1922, in Berkeley, California, to Leslie and Ethel Wilson. After earning a B.S. degree in chemistry from the University of California, Berkeley, he immediately joined the Manhattan Project. A humorous story of his first research problem highlights Jim Wilson's ability to find simple solutions to complex problems, a trait which characterized his career. When he arrived at Los Alamos, his supervisor handed him a pea-size chunk of dull grayish metal and said, “This is the world's supply of plutonium. I’m going to lunch; please brief me on its metallurgical properties when I get back.” Jim pondered his task, then put the pellet on an anvil and smacked it with a hammer, and later reported to his supervisor that it was malleable. As he recounted later, fortunately it was very impure plutonium; otherwise it would have pulverized and contaminated the entire building.
He returned to Berkeley and earned a doctorate on the theory of mesons in 1952. After a year at Sandia Laboratory in Albuquerque, he joined the Lawrence Livermore National Laboratory, where he worked until his death. He was also an adjunct Professor of Physics at the University of Notre Dame from 1996 to 2007, where he frequently visited. His expertise in computational physics was initially applied to classified projects. His work on those projects laid the groundwork for a whole category of essential tools for understanding and designing nuclear weapons. In 1968, however, he took a sabbatical year at Cambridge to study astrophysics. He applied much of his previous computational expertise to public research for the next 37 years. His professional recognition includes The Marcel Grossman Award in 1994 for work in relativistic astrophysics, and in April 2007, he was awarded the APS Hans Bethe Prize for “his work in nuclear astrophysics and numerical work on supernovae core-collapse, neutrino transport and shock-propagation. His codes re-energized supernovae shocks and launched numerical relativity and magnetically driven jets.” This recognition was particularly appropriate for Jim, insofar as Hans Bethe was a regular visitor to Livermore and collaborated with him on core-collapse supernovae. The two often pored over the output of Wilson’s codes far into the night. On one occasion, Bethe returned early the next morning, announcing (correctly) that there must be an error in the computer calculation, as it had not agreed with the computation he had done by hand overnight.
In the early 1970’s Wilson pioneered the fields of numerical relativity and numerical relativistic hydrodynamics. Besides his work on supernova collapse, which led to the mechanisms of delayed neutrino heating for supernova explosions, and the neutrino-energized bubble as a site for heavy-element nucleosynthesis, he was among the first to numerically compute collapsing magnetized rotating stars, relativistic jets, accreting Kerr black holes, and colliding binary black holes and neutron stars. Both Jim Wilson’s classified work and his work in astrophysics dealt with systems that are too complex to be fully described in any feasible computer program. Both also involve some poorly known facets of the underlying physics. In both areas, as a result, getting a meaningful answer requires an indefinable quality that could be called good taste in physics. Such good taste combines a clear grasp of the basic processes involved and their likely interplay, a feeling for what quantities will mainly determine the process under investigation, and some intuition. Jim’s success in both fields was in good measure due to good taste in physics, together with a willingness not to be daunted by the complexity of the problems.
Jim’s other great passion in life was mountaineering. Jim met his future wife, Demetra Corombos, while climbing in the Canadian Bugaboos in 1947. They were married on February 24, 1949 and enjoyed 56 years marriage and five children. Jim Wilson was known to friends and family for his mountain adventures, including annual weeklong family back-packing trips in the High Sierras, which continued a tradition established by his father in 1903. He made rock-climbing first-ascents in Yosemite Valley and Sequoia, mountaineering in British Columbia and a month-long ascent in 1967 of Hummingbird Ridge on Mt. Logan, still considered the hardest mountaineering route in North America, which has not been repeated. His winter ski of the John Muir Trail was the first done without caches.
Reproduced from Physics Today , with the permission of the American Institute of Physics. The obituary was prepared in collaboration with Wilson’s children.