I guess I’ve always been confused by the Many Worlds Interpretation of Quantum Physics and the fact that it’s taken seriously. Like is there any proof at all that universes outside of our own exist?

I admit that I might be dumb, but, how does one look at atoms and say “My God! There must be many worlds than just our one?”

I just never understood how Many Worlds Interpretation was valid, with my, admittedly limited understanding, it just seemed to be a wild guess no more strange than a lot things we consider too outlandish to humor.

    • BrainInABox@lemmy.mlEnglish
      31·
      7 months ago

      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”

        • BrainInABox@lemmy.mlEnglish
          12·
          7 months ago

          If there are many actual physical worlds out there representing all possible states of the wave function simultaneously, then the wave function couldn’t collapse because then those worlds wouldn’t exist. Each possible state of the wave function is a physical world representing that state.

          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.

          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.

          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.

            • BrainInABox@lemmy.mlEnglish
              12·
              7 months ago

              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.

              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.

              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

              No they wouldn’t, the laws of physics still apply

              “objective” in “objective collapse” at face value

              And why shouldn’t I?

              No experiment has been performed that has detected this radiation being emitted, but if it had, it still wouldn’t have falsified MWI.

              Yes, but by your standard, nothing can ever be falsified.

              I’m quite sure there’s no experiment

              You asserting it doesn’t make it true.

              From within each world: Observers see exactly what CSL predicts - apparent spontaneous wave function collapse accompanied by radiation emission (or not, in this case). The collapse looks completely real and objective to the observers, and there is no experimental way to show otherwise.

              Except there is no radiation emission unless the wave-function objectively collapses. That’s the point.

              Both frameworks ultimately make identical (observable) predictions from within each world

              No, they don’t. One predicts spontaneous radiation release, and one doesn’t.

              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.

              literally asking to prove a negative.