@Thinkerbell Actually, the multiverse is used to explain what appears in our universe to be single particle interference in phenomena like the double slit experiment. However, the interference is always with identical particles. Thus the (arguable) evidence we have from other universes show identical physical properties.

In the Many-Worlds Interpretation (MWI) of quantum mechanics, the interference pattern of a single particle (such as an electron or photon) in a double-slit experiment is explained by parallel realities interacting across the multiverse rather than a single particle acting as a wave that collapses.

... Interference Between Worlds: The particle in our universe does not travel alone. Its motion is influenced and deflected by interference with its counterparts (or the surrounding quantum state) traveling through the other slit in adjacent parallel worlds


Also see https://en.wikipedia.org/wiki/Double-slit_experiment

@ElwoodBlues

You are confusing the many-worlds hypothesis with the multiverse hypothesis.

Many-worlds posits that every possible outcome of every quantum event actually happens, resulting in many versions of this (our) universe, where the fundamental physical constants remain the same.

The multiverse posits many separate universes (perhaps each beginning with its own big bang) in which the fundamental constants are not necessarily the same as in our universe.

https://www.discovermagazine.com/are-many-worlds-and-the-multiverse-the-same-idea-4965

https://www.scientificworldinfo.com/2026/04/can-multiverse-theory-solve-fine-tuning-mystery.html

@Thinkerbell Nope. As I said Notice that word "multiverse" in there? Some versions of many worlds include the multiverse.

@TheRealBarbossa it was a generalization that inspired this post