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I'm aware of the double slit experiment and its variations, but I probably do misunderstand Many Worlds to at least some degree; how does wave collapse prove Many Worlds to be false?
Well, under Many Worlds, wave function collapse isn't a real "thing"; it's just an illusion caused by the observer becoming entangled with the wave function. Objective Collapse theories, however, propose a real physical mechanism of wave function collapse. If that's true, and there was found to be a real mechanism of collapse, then MW would be impossible, because the wave function would collapse before any "branching" could happen.
And what is there to stop the collapse from being the branch point? In one world, it collapses one way; in another, another. There doesn't seem to be any inconsistency there.
Well, because under Many Worlds, the wave-function not collapsing is the reason there are multiple branches; the wave function is the multiverse. So if the wave function has collapsed into a single, definitive state, then there is only a single, definitive universe.
Sorry, that doesn't prove that there's not actually Many Worlds out there. The whole point is that there would be a single, definitive universe state for every possible valid configuration after wave-function collapse. The reason it's unfalsifiable is that it cannot be proven currently whether or not it's a literal plurality of alternate worlds. I would also argue that if there's but one "definitive universe" state then it's not really a Many Worlds theory at all, but just a different theory of the Universe.
I'm not saying you're wrong, or that this interpretation of Many Worlds is wrong - I'm just saying we've not yet developed a way to prove it one way or another. And if we did develop that technology to prove it one way or another, that would in itself unlock a whole new world of questions to answer. Thinking about what those questions might be is worthwhile science, in my view.
I think you misunderstand me. I'm talking specifically about the Many Worlds interpretation of Quantum physics specifically, the one originally formulated by Hugh Everett. I'm not talking about just some general notion that "there might be other universes".
It's just an indisputable fact that the MWI requires their to be no wave function collapse, and if you don't understand why, you really have not learned enough about it to be in a position to declare it "unfalsifiable".
Well, I did allow for that earlier. I'm not a physicist. However, I wouldn't be so sure I don't understand why. Reading back over the thread as a whole, you're right - I did misunderstand you. Let me put it in my own words for you:
But you said above:
and
Could you link the experiments which have definitively shown objective collapse and not just an entanglement illusion? Fair warning, I may need to ask for a layman's explanation of how they proved the collapse was objective and not just the aforementioned illusion.
Essentially, yes. I think the important point is that MWI is only concerned with the multiverse that an uncollapsed wave function represents, not any other kind of multiverse that might exist in science or philosophy.
Here's a reasonably good article about them.. But to try and give a short explanation, the experiments were for a class of objective collapse theories were individual particles collapse spontaneously with a certain probability, and take any particles they're entangled with with them. The probability of any one particle collapsing at any given time is extremely low, but a macroscopic collection will collapse almost instantly, in the same way a uranium atom will take millions of years to decay on average, but a chunk of uranium sitting on a table will make your gieger counter sound like it's full of bees.
The important part though, is that - for reasons that are quite technical - the collapse of the particle actually emits a small but measurable amount of radiation, which is what the experiments were looking for.
To be clear, they didn't find it, which is bad for these theories. But if they had found it, it would have falsified Many Worlds.
Funnily enough, I found that article while reading up on MWI and was keeping it in my back pocket to compare with whatever you ended up linking.
So here's where I think we're getting tripped up. You're talking as though detecting this radiation would have falsified Many Worlds; I still think it would not. It would have created an explanatory burden on proponents of MWI, to explain where this radiation is coming from if not wave function collapse. These experiments wouldn't have been able to prove that the collapse was causing any kind of radiation emission; only that radiation emission was concurrent with it. We could conclude the collapse was the source only if all other sources were ruled out as possibilities.
Here's why: Each "world" would observe its own collapse of the wave function. The parameters of the emitted radiation - particle or wave type, energy level, charge, spin, colour, direction of travel, everything - would be different for every collapse, because every collapse is a branch point for a new world that can observe that specific collapse.
The trouble here is that you're taking the "objective" in "objective collapse" at face value. No experiment has been performed that has detected this radiation being emitted, but if it had, it still wouldn't have falsified MWI. I'm quite sure there's no experiment that can be performed that can't also be explained away with branching paths. Certainly not an experiment possible with current technology or theories.
The problem is, as I said, one of perspective:
Both frameworks ultimately make identical (observable) predictions from within each world, which is what makes MWI unfalsifiable. If you had a way to definitively show from within this world that MWI's other worlds don't actually exist, then it'd be falsifiable. The ontological claims of a theory are not what make it unfalsifiable.
Ok, well now you've basically argued that falsification in general is impossible, for anything. Just like geocentrists could always add more epicycles to explain the motion of the stars, any theory can add more post-hoc explanations for any observations. This isn't a standard you would apply to anything else, so I don't know why you're applying to MWI.
No they wouldn't, the laws of physics still apply
And why shouldn't I?
Yes, but by your standard, nothing can ever be falsified.
You asserting it doesn't make it true.
Except there is no radiation emission unless the wave-function objectively collapses. That's the point.
No, they don't. One predicts spontaneous radiation release, and one doesn't.
literally asking to prove a negative.
English comprehension fail, no I didn't. I said you can't prove other works exist or not if you can't access anything other than this universe's information, which is true, because if you can't access anything other than this universe's information there's no experiment to run on information about other worlds. This stems from not being able to observe those worlds by which to gather information about them, which is quite important to the scientific method.
You think "the laws of physics" state there's only one outcome for every trait of a radio wave or excited particle? Because that's what your statement here means, since you're disagreeing with me. We're talking about how everything is a cloud of possibilities and you want to tell me now that every trait and path is predestined? That's just wrong.
Because reality is not objective, duh. Quite literally what we've been talking about this whole time.
Still as wrong when you said it here as at the start.
I was being polite. Show me the experiment, and this time don't just link any old shit in the hope I won't read or understand it. Despite my words, I know what I know, and you don't get to condescend to me without proving me wrong. Which you haven't done yet, due to the aforementioned failures in your English comprehension.
There's no radiation emission at all that we've observed, but even if there were, you can't just demonstrate something happening around the same time and call it causality. You have to the show the radiation didn't come from another source, and anyone who disagrees with your conclusions has to show it did, and then we all get together and pick it all apart in peer review until we've decided whose argument is the best-supported.
Which is like now, but you're not showing any evidence of these "objective experiments" we've been running that supposedly prove anything about or have access to information from outside our universe.
Explain how you plan to show that the spontaneous radiation release was not a result of being entangled with the thing you're observing. Your whole argument rests on information from this world, I'm blown away you don't see the fault in it.
Yeah you're right, let me rephrase: if you had a way to definitively show from within this world that MWI’s other worlds DO actually exist, then it’d be falsifiable.
There. Now go ahead and prove that other worlds exist.
You spent a lot of words to say you don't understand that we don't live in an objective universe, or what falsifiability really is. I'm just willing to allow that I might be wrong even when I'm not, and you aren't because you're so certain you're right you can't see what you're actually saying.
I'm done with this conversation now; I hope you go do some reading on the scientific method to address these shortcomings, because I am positive you're not going to do the one thing you need to (which, again, is just to show the objective experiments you're talking about, rather than condescending to and insulting me).
I want a paper that analyses information observed from other worlds, which yours DID NOT. Try taking your own advice to that other person in this topic, and read what I wrote.
Okay, apparently I need to take you to school before I go to work. I didn't realise it was my turn with you this week. Just to catch you up: https://www.nobelprize.org/prizes/physics/2022/advanced-information/
(That bit, by the way, is why I'm right and you're wrong. Not experimentally testable? Not falsifiable. Period.) And
Now I'll be blocking you. Happy reading.
I think you missed the part where I said I'm done.
Seems like it's splitting hairs and saying the "many worlds" part of MWI doesn't count, as that is only a prediction not postulated.
No? I'm not sure how you got that from my comment
I'm taking about the linked page.
I mean, to be fair that is what the linkes page says, but people are misunderstanding the hypothesis everyone calls many worlds (also what the page says) as Many worlds is just a follow up of the theory not the theory itself.
Like Einsteins Relativity didn't say in the theory that we would be able to predict Mercury's orbit, but it comes from it.