Simulation Theory

[jack black]

Simulated reality is the hypothesis that reality could be simulated—for example by quantum computer simulation—to a degree indistinguishable from "true" reality. It could contain conscious minds which may or may not be fully aware that they are living inside a simulation.

The simulation hypothesis proposes that all of reality, including the earth and the universe, is in fact an artificial simulation, most likely a computer simulation. Some versions rely on the development of a simulated reality, a proposed technology that would seem realistic enough to convince its inhabitants the simulation was real. The hypothesis has been a central plot device of many science fiction stories and films.

[Mystic Wolf]

This is pretty interesting

[William J. Coblentz]

One S & S Fantasy author posited the theory in other terms, that the multiverse could be the dream(s) of a god(dess). It works out essentially the same, regardless of the wording...