I was reading a paper written by Nobel laureate George Smoot, Go with the Flow, Average Holographic Universe, which assumes the holographic principle as true and conjectures that our universe would be encoded on the "surface" of an apparent horizon as the weighted average of all possible histories. In that way, as he says at the end, there would be one world (or universe) that would be the average among all possible worlds.
However could more than one apparent horizon exist?
If the answer is affirmative,then wouldn't there be other universes "encoded" on those other apparent horizons if that was the case?
And could some of these other universes be the result of the realization of one particular history (or a particular set of histories) instead of the average of all possible histories?