A tribute to Oscar Buneman pioneer of plasma simulation

Until his recent passing, Oscar Buneman (of Stanford University) held an undisputed position as a leader in the field of computational plasma physics. He was one of the first individuals to apply the infant tool of numerical modeling to practical problems in vacuum electronics. Over the decades, he remained at the forefront in proposing, studying, and implementing a dizzying variety of novel concepts and algorithms to more efficiently study complex plasma behavior. After early breakthroughs in algorithms for the direct numerical solution of Poisson's Equation, he moved on to studies of finite element analyses, numerical noise suppression via Fourier space filters, variational principle formulations, quadratic splines, multistream models, etc. He was among the first to successfully complete a fully relativistic, 3-D electromagnetic P.I.C. code in the late 1970s with, of course, all key routines coded in Cray assembly language. A key part of Oscar's genius lay in his unwillingness to accept the traditional boundaries of his field. He knew the importance of seeking knowledge from all related fields such as mathematics and computer science as well as physics and electrical engineering. This openmindedness led to such insights as his application of nearly identical codes to both plasma as well as vortical fluid flow problems with merely a few sign changes and scaling modifications. Colleagues, coworkers, and friends of Oscar will present their remembrances of his important contributions to the field. This plenary address was to have been delivered by Oscar, himself, under the title, Simulation From Electron Devices to Cosmic Plasmas. The authors cannot hope to match what he, himself, would have presented, but they will reflect the esteem felt for a visionary scientist who will be greatly missed