On Thu, Feb 6, 2025 at 11:49 AM Quentin Anciaux <[email protected]> wrote:
> Bruce, > > You’re making a distinction between single-event probabilities and > repeated trials, but you’re not addressing the core issue: in a > single-history universe, probability is only ever descriptive, not > explanatory. You claim that if an asteroid has an 80% chance of impact but > doesn’t hit, then the 20% chance was simply realized. But this explanation > is entirely retrospective—it tells us nothing about why this history, > rather than any other, is the one that unfolded. > That is the nature of random events. It seems that your real objection is to randomness, events that have no simple mechanical explanation. That is quantum mechanics, and you just have to get used to it. You say, "assuming the calculations were accurate, then there certainly was > an 80% chance of hitting, and a 20% chance of missing." But in what sense > was that 80% ever real? In the only history that exists, the asteroid never > had an 80% chance of hitting—it always had a 100% chance of missing because > that’s what happened. The probability was just a number assigned before the > event, with no actual force in determining the outcome. > I think the calculations are based on prior experience. They are real enough, not just empty air. In a multiverse framework, probabilities are grounded in actual > distributions across histories. The 80% means that in 80% of branches, the > asteroid hits, and in 20%, it misses. This gives probability an explanatory > role—it describes the structure of reality, not just an arbitrary number > assigned to something that never had a chance of happening. > Unfortunately, it is well known that branch counting is a failed enterprise in quantum mechanics. So the claim that something or the other is true in 80% of the branches is just empty rhetoric. You claim that MWI has no way to connect probabilities to the wavefunction, > but that’s false. The structure of the wavefunction naturally assigns > measure to branches, > Does it now? And how does it do that? You have a well-developed ability to make endless unevidenced assumptions and bend them to your will. Start trying to prove some of this! and those measures correspond to the squared amplitudes of the > coefficients—the Born rule emerges from this structure. > It does not without many additional assumptions. The attempts to derive the Born rule from Everett have all failed. You keep asserting that probabilities in MWI are meaningless because "all > possibilities happen," but that’s only true if you ignore the fact that > measure matters. Not all branches are weighted equally, and the frequencies > of outcomes reflect those weights. > But you have not shown how these weights arise, or how outcomes depend on these 'weights'. The issue isn’t whether we can calculate probabilities in a single-history > world—it’s whether those probabilities have any real ontological meaning. > You claim that in a single-history world, probabilities "just work," but > that’s not an explanation. It’s just a way of pretending that numbers > assigned before an event have some deeper reality when, in truth, they > don’t. In the end, the only thing that exists is the one history that > happens, and everything else was just an illusion of possibility. > You are still looking for an 'explanation' of random events. You will look in vain, because no such explanation can be forthcoming. Bruce -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAFxXSLSoueSm74SRU0nie_b%3D%3DCDft6rWboAJPMKfyNLUbHAhOA%40mail.gmail.com.
