Empirical Evidence for Multiverse

[Whateverist]

It's not a theory, it's a hypothesis. Actually a group of hypotheses. Like all valid hypotheses, they attempt to explain observations in a way that is at least potentially testable

That was my point in the OP. By their very nature, Multiverse theories exclude that possibility.

By their very nature? Really!

I always thought so, at least if we accept that the (our) universe is expanding at a rate which rules out ever contracting.  It is hard to imagine how an adjoining-verse would ever intrude upon our own in a way that would be perceptible from our perspective or conclusively inferable from anything we can detect.  But then I always was a pessimist.

On a separate point, Quantum, don't you doubt the idea that every cell of a multiverse may behave according to laws/patterns that may vary randomly between cells?  It seems to me more likely that whatever underlying substrate gives rise to cells would be common and behave homogeneously, with any variation being accounted for by the rules of organizing principles of the mega-verse .. which we simply don't know.

[GrandizerII]

So what testable predictions does MWI make that other quantum world interpretations do not? That article just dodges the question rather than provide a satisfactory answer. I don't care about "old" and "new" predictions, I just want to know about the unique predictions for each interpretation.

Don't get me wrong: I think MWI is logically the most reasonable interpretation of the quantum world thus far, but I still don't see how it is testable.

Testable predictions of MWI? Interference for one. Some details here: http://lesswrong.com/lw/pd/configuration...amplitude/

But I would also look at the Carroll and Deutsch links I posted above.

I said unique. Interference is predicted by others as well.

Let me rephrase it another way: what tests or experiments would you conduct to show that MWI is the true interpretation?

[Amine]

I said unique. Interference is predicted by others as well.

Let me rephrase it another way: what tests or experiments would you conduct to show that MWI is the true interpretation?

Is it? Honestly I'm not an expert, but it seems more like interference is observed in other interpretations but explained in many worlds (without contradiction or magic). From what I understand it is kind of like creationism saying fossils could have been placed there by God or could be artifacts of our minds or something like that.

[Alex K]

MWI makes no predictions that the pragmatic copenhagen prescription doesn't also make. I just find it plausible because it is so simple in a way.

[Amine]

MWI makes no predictions that the pragmatic copenhagen prescription doesn't also make.

Doesn't the Copenhagen interpretation actually add extra to the theory--namely entirely separate physics dealing with observation? Why and how does the wavefunction collapse?

[Alex K]

Yes, exactly. And it does not explain what happens to a physical system, it only tells you the (probabilities of) outcomes. That's why it is so unsatisfactory philosophically.

The schroedinger equation already automatically gives you many worlds in your wave function. Copenhagen then contains an artificial prescription how to discard all but one of them as soon as the - somewhat arbitrarily chosen - observer is affected.

[TheRealJoeFish]

Just now noticed that today's post on my favorite webcomic is rather germane:

[Amine]

Geordi Rose of D-Wave explains here how quantum computers use decoherence and interference to outsource computation to other universes: https://www.youtube.com/watch?v=PqN_2jDVbOU

Pretty awesome stuff.

[IATIA]

Everything consists of waves. Particles do not exist in a physical sense. They are but an intersection of alternate probabilities or "universes".