More or less. There’s a bit more nuance to it, and I was thinking particularly of the case of entangled particles at a distance rather than a self-interfering particle through a slit - but it probably resolves down to much the same mathematics.

Bell’s inequality proves the simple (‘realist’, above) option can’t be true, but the Copenhagen Interpretation is the most accepted interpretation of the alternative. Wikipedia lists three such interpretations, and IIRC “many worlds” is a separate one to the Copenhagen Interpretation. Though again, it’s a bit more nuanced. When I was studying, I think they basically assumed Copenhagen, though not treating that entirely as settled fact, and leaving other interpretations as niche.

I see. Thank you for your more explanatory reply. I must not hang out in the right circles, because I haven’t seen that enough to see it as a cliché. Perhaps the commenter was not dismissing multiverse theory because of a gut reaction, but because they’re fed up themselves with popular and un-falsifiable speculation being treated as science.

The incredible thing with these weird results is they are falsifiable - this “spooky action at a distance” that famous pre-redditor Albert dismissed as nonsense. Bell’s inequality, that lies at the heart of the trouble, is experimentally demonstrable.

But there’s a gap between that science and the interpretations of it. And maybe coming from they popular end, it’s easy to see the wilder speculations as nothing more than unprovable imagination.

But in the end, after re-writing much of my comment, I have to concede the point. I feel you’ve made a bit of a straw man to attack, but I agree a thing can seem unapproachable scientifically - non-falsifiable - but still be valid science. Even in this area, IIRC, part of the debate over the main quantum mechanics interpretations is quite whether they can be falsified or experimentally differentiated: and that itself takes time and logic and mathematics… it takes science!

You mean the post at the top? Or the comment you replied to? Either way I don’t really see the cliché.

Do you mean that something being non-falsifiable making it non-scientific is a cliché? That’s how science works: by having theories that can be differentiated with experiment.

Or, of the post, that multiverses contain every conceivable universe, then why anti-intellectual, when it’s just a silly joke?

But there’s a universe where you aren’t.

Aha! The one from Cheshire!

I think you mean, multiverses that every multiverse that doesn’t contain itself. In which case, obviously yes. And it’s made up entirely of barbers.

Which is the anti-intellectual cliché?

It’s not purely a wild, non-falsifiable idea. It comes from a theory to reconcile the very-much-falsifiable-but-not-falsified results of quantum mechanics. IIRC there are three main theories to interpret the results and all of them are down-and-out weird. Last I looked, one of them at least is controversial about whether or not it could (in principle) be experimentally differentiated from the others.

Or am I getting this completely wrong?

I mean, the whole premise is getting this completely wrong. The actual physics idea behind multiple universes is that every possibility in specific quantum events happens, each one being in a separate, ‘parallel’, universe where everything else in the universe is exactly the same. All the laws of physics stay the same, just the results of all the cumulative random possibilities are different.

This is also not the only explanation of that strange phenomenon in quantum mechanics.

Infinite countries. Which mumblemumble clearly makes it all work.

It’s being suppressed by Big Paper. Or by Big Universe.

Quantum results are hard to explain, but proven (by experiment) to be real. There’s a particular mathematical/logical definition of something being ‘real’ and ‘local’, that I’ve still only half got my head around, and it should be true but isn’t.

The main experiment is two particles that, if you check one, it affects what you’ll see in the other in a particular, but subtle , way. And it’s proven mathematically impossible to find an explanation where they don’t either communicate faster than the speed of light (so, not ‘local’) but the effect actually happens (‘real’).

The trick is in the statistics - the pattern of results - that match up between the two particles in this very particular way. And one way to explain it is that different options are also happening, but in a different universe - i.e. every time two different things could happen, reality splits into two realities, one where this happens and one where that happens.

That’s for specific quantum events, but some think those such quantum events underlie all choices and possibilities in reality. So, scale up that idea and you get ‘infinite’ (actually just very very many) parallel universes, one for every possibility that could ever have happened, branching off into more each time a (quantum) choice happens.

If there are an infinite number of road junctions, there must be one that reaches a place where road junctions don’t exist.

Hello all, I made the jump.

And I saw the avatar for the community, and for this fleeting moment thought it was a post about successfully making some particularly hard jump in supertux2.

Right…?

Is this why there was all the hate against 3rd party apps recently?