## Nicholas C. Metropolis

Link: http://www.cbi.umn.edu/oh/display.phtml?id=81

Nicholas Metropolis begins with his recollections of John von Neumann and his interaction with him at Los Alamos National Laboratory, starting in 1943. He worked on shock problems with von Neumann, and discussed various computing problems. Von Neumann brought news, the most important and exciting of which was of the development and details of the ENIAC. In an arrangement made by von Neumann, the Ballistics Research Laboratory in Aberdeen and Los Alamos National Laboratory ran a problem to study thermonuclear ignition. Metropolis comments that von Neumann learned most of what he new of practical computing at Los Alamos. He discusses various kinds of problems that von Neumann worked on with people at Los Alamos, including implosion, shaped charges, neutron diffusion and Monte-Carlo methods. Monte-Carlo methods were of interest for various practical problems; one of the earliest Metropolis notes was the suggestion that they could be used to solve the Schrödinger equation. The first ambitious tests of Monte-Carlo were conducted at Aberdeen on the ENIAC. He remarks on the previous knowledge of Enrico Fermi of Monte-Carlo type methods and his subsequent interest and work when electronic computing became available. Metropolis concludes with a discussion of von Neumann's interests in numerical methods, particularly for nonlinear partial differential equations of hydrodynamics.

Key words: shock problems, Mark I, ENIAC, thermonuclear ignition, ORACLE, implosion, shaped charge, Monte-Carlo Method, neutron diffusion, numerical methods, Courant-Friedrichs-Lewy conditions, artificial viscosity, nonlinear problems in hydrodynamics

Funding agency: U.S. Department of Energy

Time frame: 1940's, 1950's, 1960's

People: John von Neumann, Stan Frankel, Edward Teller, Stan Ulam, Robert Richtmeyer, Seth Neddermeyer, Enrico Fermi, Olga Ladyenskaya

Locations: Los Alamos National Laboratory, Ballistics Research Laboratory, Harvard, Institute for Advanced Study, Argonne National Laboratory

Copyright: Charles Babbage Institute, Center for the History of Information Technology

Oral History Collection, http://www.cbi.umn.edu/oh/