sponsored by the Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA, September 9-12, 1989 ; editor, Howard Gutowitz
editors, Doyne Farmer, Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM, 87545, Tommaso Toffoli, MIT Laboratory for Computer Science, Cambridge, MA, 02139, Stephen Wolfram, the Institute for Advanced Study, Princeton, NJ 08540, USA