N. W. Ashcroft
Neil Ashcroft was born in London, England, shortly before World War II. His first degrees, in physics and mathematics, were awarded by the University of New Zealand; his Ph.D., in theoretical condensed matter physics, was obtained at the Cavendish Laboratory, Cambridge, in 1964 (with Dr. J. M. Ziman). This was followed by a post-doctoral appointment at the University of Chicago after which he moved to Cornell University and where, after more than four decades, he is presently Horace White Professor of Physics, Emeritus. His research interests lie in the theories of many-particle assemblies, both quantal and classical, and include the studies of electronic and structural order in systems where density can be systematically increased by both static and dynamic means. Photograph: Courtesy David Mermin.
We can generally understand the way simple chemical combinations arise by assuming a standard valence structure for the elements, but a high-pressure study suggests that the rules for hydrogen may not be so easily pinned down.