# NYU Courant Mourns the Loss of Professor Jerry Percus

Our colleague Jerry Percus passed away on March 7 at the age of 94. Jerry came to the Courant Institute in 1958, after obtaining his doctorate at Columbia and working for several years at the Stevens Institute of Technology. Jerry was internationally recognized for his pioneering work in statistical mechanics and combinatorics, and made seminal contributions to our understanding of fluids and biomathematics.

In addition to the famous Percus-Yevick Equation for the radial distribution function of fluids, he alone or jointly with students and coworkers, made important advances in all aspects of statistical mechanics. He was the first (or among the very first) to study "consistency" of approximate one and two particle classical distributions and quantum density matrices. This led to the Percus-Yamada condition in the former. He derived and solved equations for the velocity correlation function of fluids. He was the acknowledged master of the statistical mechanics of non-uniform fluids. His analysis of non-isotropic fluids in terms of appropriately designed isotropic ones contributed much to this subject.

In recent decades Jerry's interests turned to pioneering studies in biomathematics, in particular genome analysis and developmental biology. Many of his papers were in collaboration with his late wife, Ora. Jerry's unique and highly creative perspective on a wide range of problems in physics, mathematics, and biology will be greatly missed.