> Further, simulating atoms requires more atoms. In other words there are impossible problems Our universe has 10^70 atoms (or whatever). This is an arbitrary

> Further, simulating atoms requires more atoms. In other words there are impossible problems Our universe has 10^70 atoms (or whatever). This is an arbitrary number. Maybe in the host universe there are 10^700000000 atoms, and 10^70 atoms are what fits inside a small "tenis ball" from that universe. BTW, we are already running pretty accurate physicals simulations, if only for extremely short periods of time and small spaces - https://en.wikipedia.org/wiki/Lattice_QCD https://en.wikipedia.org/wiki/Lattice_QCD