[lagrange77]

It sounds like he is talking about an actual simulation:

> Basically, his idea was that if we progress far enough technologically, we'll probably end up running a simulation of our ancestors. Give those simulated ancestors enough time, and they'll end up simulating their own ancestors. Eventually, most minds in existence will be inside layers of simulations — meaning that we probably are too.

> What they mean is that this three dimensional reality we're experiencing is a projection of some sort of higher dimensional reality.

I think, that's also true for holography.