Structures and Self-Replication — Machines That Copy Themselves
Before DNA was understood, a mathematician asked whether a machine could build a copy of itself — and answered it with a cellular automaton. Von Neumann's self-reproducing automaton proved that self-replication is possible in principle, and in doing so anticipated the logic of biological reproduction. This post is about the structures cellular automata can build, the deep question of self-reproduction, and what it taught us about life itself.
Von Neumann used a cellular automaton to prove a machine can build a copy of itself — via a universal constructor and a description that is both interpreted and copied, exactly how DNA works, worked out before DNA's role was understood. CA structures from gliders to self-replicating loops, and what they taught us about life.