Their abstract starts, "Observable consequences of the hypothesis that the observed universe is a numerical simulation performed on a cubic space-time lattice or grid are explored." They're not saying that's how it works, but since that's one of the few ways we can imagine simulating the universe, it's reasonable to look for its signature.
I've always thought there must be better ways of simulating the universe than starting a 3D CA at the big bang and running it forward a few billion years in femtosecond increments until something interesting happens.
I've always thought there must be better ways of simulating the universe than starting a 3D CA at the big bang and running it forward a few billion years in femtosecond increments until something interesting happens.