Max Tegmark's Theory of Everything
According to Tegmark, every last formal system on the tree of mathematics is endowed with physical existence. Every last formal system corresponds to an actual universe.
Tegmark has extended the Copernican principle beyond our Universe to an infinite set of universes. Not only is there nothing special about our status within the Universe, he claims; there is nothing special about the status of our Universe within the infinity of universes that constitutes the multiverse.