The many-worlds-theory which some argue is more philosophical than scientific is a point of scientific controversy as it’s unprovable. It is the theory that (in essence) parallel universes exist. Some argue it’s true from the string theory point of view, and the quantum mechanics approach, both of which one could only prove with math and not empirical data, this is partially where the idea that it’s philosophical comes from. Regardless of the type of, say, multiverse theory people argue (these are all very similar), they are only provable within the clear world of mathematics. This means that it’s impossible to even conceive an experiment or question whether scientists have been cheating. Still, the mathematical route to proving these questions is kind of an experiment in its own way. The theoretical physicists start out with question and then they get a hypothesis and then they test out mathematically. I personally choose to believe that there may be other universes or versions of our world out there, or there is simply so much universe that it’s almost the exact same thing as have alternate realities.
