[bawolff]

The paralell universe thingy or the "multiple worlds" interpretation (which is what i assume you mean) is one of the competing philosophical explanations for what is going on during quantum mechanics. Like most topics in metaphysics, there is no evidence either way, and there are competiting interpretations that are just as good (but don't capture the imagination in the same way). Its based off the cat experiment in that its trying to explain what is happening there metaphysically, but the parallel universe interpretation doesn't make any testable predictions beyond those made by quantum mechanics, so neither the experiment nor any other experiment, proves it.

Any sort of visiting paralell universes stuff is pure sf.

[JohnStrangeII]

The Everett interpretation of quantum mechanics is not "metaphysics", the theory is principally testable and falsifiable by empirical data. The experiments needed to test it are just not yet feasible. Sean Caroll has written a nice blog post about this in 2015 [1].

[1] https://www.preposterousuniverse.com/blog/2015/02/19/the-wro...

[chadcmulligan]

yes, thanks, thats what I meant. While I'm here, something I've always wondered about the multiple worlds interpretation is where does the energy come from for all these parallel universes? Like if each possible event causes a split then haven't we just doubled the energy we started with? since we've created a whole new universe.

[rcxdude]

I don't think there's new energy: the 'new universe' is just a part of the evolving wavefunction, which conserves energy.

[hartator]

Yes, and there is billon of quantum events happening right now in each cubic inches of air around you. So billions of universe literally from thin air. Multiverse is fun but absurd.

[pa7x1]

You seem to argue from an economic point of view, as if it was too "expensive" or "wasteful" to have all those universes. But MWI doesn't add any postulates to QM, in fact it is the simplest of the interpretations and a direct translation of what the math of QM says. All those universes are as "expensive" as the quantum mechanical state superposition they represent, and the superposition is a central tenet of QM and thoroughly tested. Your conclusion could be rephrased as "quantum superposition is fun but absurd".