ABSTRACT
Stanislaw Ulam investigated in the 1940s. He had access to early computers at Los Alamos, so the problems weren’t as tedious as they are on graph paper. He varied the rules so that cells could turn on or off and investigated other initial conditions. He even used grids made up of triangles, and hexagons. In yet another direction, he investigated three-dimensional cellular automata. Many of these examples illustrated how simple rules can give rise to complex results. This is a phenomenon, although at the time Ulam was studying cellular automata, the term “fractal” had not yet been coined. When von Neumann discussed the problem with Stanislaw Ulam, the latter suggested that he pursue it more abstractly with cellular automata, instead of actual physical parts. Although far from simple, von Neumann’s creation was a universal replicator; it could make a copy of anything, including itself.
