Part 5/7:
Simulations also provide a way to explore the idea of a "multiverse" - running multiple versions of a simulation with slightly different parameters. This connects to the concept of the "many-worlds" interpretation of quantum mechanics, where parallel universes exist.
As quantum computers become more powerful, they may be able to directly simulate quantum systems in ways that classical computers can't. This could shed light on the nature of quantum gravity and the early universe, where quantum effects were dominant.