I guess I’ve always been confused by the Many Worlds Interpretation of Quantum Physics and the fact that it’s taken seriously. Like is there any proof at all that universes outside of our own exist?
I admit that I might be dumb, but, how does one look at atoms and say “My God! There must be many worlds than just our one?”
I just never understood how Many Worlds Interpretation was valid, with my, admittedly limited understanding, it just seemed to be a wild guess no more strange than a lot things we consider too outlandish to humor.
Multiverse and many worlds interpretation are two different things.
The idea of multiverse is that there are many other universes existing in parallel with ours. Either the universes are created through different big bangs, or maybe the universe is constantly splitting into many other universes. This is mostly science fiction.
MWI is one of many competing ideas to help coming to terms with the counterintuitive nature of quantum physics. A particle can be in many places at once when not observed. Once it’s observed, it chooses to stick in one place. MWI is one interpretation of why this is happening.
I’m pretty sure the multiverse theory is baked into the big bang theory and cosmological theories, so I wouldn’t necessarily call it mostly science fiction.
Cosmological hypotheses suggest universes with different initial conditions are possible (different space-time geometries, different elementary particle masses, etc.). The big bang theory suggests multiple universes (not just ours) with different initial conditions were formed due to eternal inflation. As the multiverse continues to undergo this eternal inflation, there forms pockets where the inflation has ended and is “hospitable”. Our observable universe would be an example of such pockets, but since inflation is eternal, there should be many of these pockets.
https://www.cam.ac.uk/research/news/taming-the-multiverse-stephen-hawkings-final-theory-about-the-big-bang