Day and Night (cellular automaton)

Day and Night is a cellular automaton rule in the same family as Game of Life.

It was invented and named by Nathan Thompson in 1997, and investigated extensively by David I.

The rule is given the name "Day & Night" because its on and off states are symmetric: if all the cells in the Universe are inverted, the future states are the inversions of the future states of the original pattern.

Although the detailed evolution of this cellular automaton is very different from Conway's Game of Life, it exhibits complex behavior similar to that rule: there are many known small oscillators and spaceships, and guns formed by combining oscillators in such a way that they periodically emit spaceships of various types.

This theoretical computer science–related article is a stub.