Brent, You're arguing that probabilities in a single-world framework are as real as those of observed events because they are derived from the same equations. But if only one history ever happens, then unrealized possibilities are just numbers in a calculation, not something that ever had a chance of being real. The theory predicts probabilities, but what actually occurs is just one unique sequence of events. The rest—no matter how formally predicted—never existed in any form beyond the equations.
You claim that this does not imply determinism, but the fact remains that only one history ever unfolds. Whether the process is called "random" or not, in practical terms, there is no actual underlying ensemble of events—there is just the one sequence that reality plays out. That makes probability, in this framework, purely descriptive of an imagined set of possibilities that never had any ontological status. You say that unrealized events are "part of reality probabilistically," but what does that even mean when they never actually happen? If an event is assigned a 60% probability but never occurs in the only history that exists, then in what sense was it ever a real possibility? It was just an abstract calculation with no actual link to reality. You keep referring to long strings of experiments as if an infinite series of trials is guaranteed to sample all possibilities—but in a finite universe with a unique history, that is simply not true. Your attempt to equate probability with other concepts like energy or entropy fails because those are directly observable and quantifiable properties of physical systems. Probability, in a single-history framework, is not a property of the world—it’s a mental construct we impose on it. It’s not like energy or momentum; it’s a way of reasoning about things that will never actually exist. MWI, on the other hand, does not set all probabilities to 1 arbitrarily. It gives probability a real foundation by making it about relative frequencies across real histories. There, probabilities describe distributions of actualized outcomes, not abstract unrealized ones. In contrast, in a single-world view, probability is just a way of pretending that things that never existed somehow mattered. That is the contradiction you keep glossing over. Le mer. 5 févr. 2025, 19:56, Brent Meeker <[email protected]> a écrit : > > > > On 2/4/2025 11:38 PM, Quentin Anciaux wrote: > > Brent, > > You say that unrealized possibilities are what probabilities quantify, but > in a single-history framework, those possibilities never had any existence > beyond the formalism. > > I don't know what "formalism" means in that context. When you calculate > probabilities of events in QM the events are not "formalisms". They are > implied by the same theories and mechanics that attributes possibility to > the events that were observed. And on other occasions they the events that > happen. So they are not mere formalism, their possibility and probability > are as real as the possibility and probability of the observed events. > > If only one history is real, then all other possibilities were never > actually possible in any meaningful way—they were never real candidates for > realization, just mathematical constructs. That’s not an emotive argument; > it’s pointing out that the entire notion of probability in such a framework > is detached from anything real. > > If probability is supposed to quantify real possibilities, then in a world > where only one history exists for all eternity, what exactly is being > quantified? If an event with a calculated probability of 50% never happens > in this one history, then its true probability was always 0%. > > That's contrary to the meaning of probability. You are assuming > underlying determinism. You seem to conceive of probability as always > being 1 or 0, which is the same as denying the very concept of probability > > Your framework claims to allow for multiple possibilities, but in > practice, it only ever realizes one, making the rest nothing more than > empty labels. > > It's not "my framework", it's the theory of probability. I think you are > confused by the fact that probability theory has many applications. You're > stuck on the application to ignorance in a deterministic case. But QM is > not deterministic. The probabilities don't refer just to ignorance. Just > because there is a single world doesn't make it a deterministic world. In > fact MWI has more trouble representing probabilities. > > > And you assert that alternatives have a "grounding in reality"—but what > does that mean in a framework where they never actually happen? > > It means that the same theory that predicted the thing that happened with > probability 0.3, also predicted the thing that didn't happen with > probability 0.6 and this theory has been verified by finding that in long > strings of experiments the latter happens twice as often as the former. > > If they had a genuine grounding, they would have to be part of reality in > some form, even if only probabilistically. > > I'm telling you they are part of reality probabilistically. What do you > mean by that phrase, if not what I've been saying? > > But in a single-history framework, that never happens. The probabilities > exist only in the mind of the observer, with no external ontological > reality. They are tools that describe nothing but a retrospective > justification of what already happened. > > Energy, moment, entropy, gravity...you could say that they are all just > tools in the mind of the physicist with no external ontological reality. > They are just terms in our mathematics. > > > The supposed "problem" in MWI—that all possibilities are realized—actually > solves this issue. It gives probabilities a real basis in the structure of > the universe rather than treating them as abstract bookkeeping. > > No, according to you they set all probabilities to 1. > > The probabilities describe real distributions across real histories rather > than referring to things that were never real to begin with. > > MWI doesn't distribute across histories. It asserts that all > possibilities occur in each event "with probability 1". That's why the > assignment of probabilities is a problem for MWI. > > Brent > > > The single-world view wants to use probability while simultaneously > denying the existence of the things probability refers to. That’s not just > emotive talk—it’s a contradiction at the foundation of the framework. > > Quentin > > Le mar. 4 févr. 2025, 23:22, Brent Meeker <[email protected]> a > écrit : > >> >> >> >> On 2/4/2025 11:38 AM, Quentin Anciaux wrote: >> >> The fundamental absurdity of single-history frameworks becomes clear when >> we consider the reliance on theoretical constructs that, by definition, >> never exist and never will. How can one justify using mathematical tools >> that invoke nonexistent possibilities to explain a reality where only one >> sequence of events is ever realized? If something never existed, has no >> causal influence, and will never exist in any possible future, how does it >> play any role in explaining what does exist? >> >> This contradiction is evident in interpretations like Bohmian mechanics, >> where the pilot wave guides particles but remains completely unobservable >> and uninteractive beyond that role. It’s an invisible, untouchable entity >> that affects matter but is never affected in return—something that is >> functionally indistinguishable from the pure abstractions of probability >> waves in a single-world interpretation. In both cases, explanations rely on >> constructs that have no true existence beyond their mathematical form. >> >> A single-history universe that leans on unrealized possibilities to >> justify probability >> >> "Justify"?? Unrealized possibilities are what probabilities quantify. >> If all possibilities were realized the wouldn't have probabilities assigned >> to them...exactly the problem that arises in MWI. >> >> is making an implicit appeal to something that doesn’t and will never >> exist. It treats the wavefunction as a real tool for calculating outcomes >> while simultaneously denying that the alternatives it describes have any >> grounding in reality. This is the absurdity: how can something that never >> existed be part of an explanation for what does? >> >> That is just a lot of emotive talk. All the alternatives have a >> "grounding in reality"; that's what makes the possibilities with definite >> probabilities. >> >> Brent >> >> >> In contrast, in a many-worlds framework, all possibilities exist and are >> real branches of the wavefunction, providing an actual basis for >> probability. The probabilities are not just mathematical conveniences; they >> describe distributions of real outcomes across real histories. This removes >> the need for metaphysical hand-waving about non-existent possibilities >> influencing reality. >> >> If physics is about describing reality, then relying on things that are, >> by construction, eternally non-existent to justify observed phenomena is >> conceptually incoherent. It is an attempt to have it both ways—to use >> abstract possibilities when convenient while denying their reality when >> inconvenient. That contradiction is why single-history frameworks >> ultimately fail to provide a satisfying foundation for probability and >> existence itself. >> >> Quentin >> >> Le mar. 4 févr. 2025, 19:03, John Clark <[email protected]> a écrit : >> >>> >>> On Tue, Feb 4, 2025 at 12:56 PM '[email protected]' via Everything >>> List <[email protected]> wrote: >>> >>> *> Bohmian mechanics v Everett-DeWiit-Wheeler? * >>>> *For Carroll, it probably means they're the same. Indistinguishable. * >>>> >>> >>> *This is what I said about that about a month ago: * >>> >>> >>> *Pilot Wave Theory keeps Schrodinger's Equation but needs to add another >>> entirely new very complicated equation called the Pilot Wave Equation that >>> contains non-local variables. When an electron enters the two slit >>> experiment the Pilot Wave in effect produces a little arrow pointing to one >>> of the electrons with the caption under it saying "this is the real >>> electron, ignore all the other ones". The Pilot Wave does absolutely >>> nothing except erase unwanted universes, it is for this reason that some >>> have called Pilot Wave theory the Many Worlds theory in denial. * >>> >>> *The Pilot Wave is unique in another way, it can affect matter but >>> matter cannot affect it, if it's real it would be the first time in the >>> history of physics where an exception to Newton's credo that for every >>> action there is a reaction; even after the object it is pointing to is >>> destroyed the pilot wave continues on, although now it is pointing at >>> nothing and has no further effect on anything in the universe. Also, nobody >>> has ever been able to make a relativistic version of the Pilot Wave >>> Equation.Paul dirac found a version of Schrodinger's Equation that was >>> compatible with special relativity as early as 1927. * >>> >>> *John K Clark See what's on my new list at Extropolis >>> <https://groups.google.com/g/extropolis>* >>> 8b0 >>> >>> -- >>> 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/CAJPayv3JL9f40jD-4qG0ry6z38ZtVysrh9RhE%2BDirJrSWzaX-w%40mail.gmail.com >>> <https://groups.google.com/d/msgid/everything-list/CAJPayv3JL9f40jD-4qG0ry6z38ZtVysrh9RhE%2BDirJrSWzaX-w%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> 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/CAMW2kAopDs_qGcSEgaZJdrDUu7qgMzWgvNbE4EPFgw5pxRBQcA%40mail.gmail.com >> <https://groups.google.com/d/msgid/everything-list/CAMW2kAopDs_qGcSEgaZJdrDUu7qgMzWgvNbE4EPFgw5pxRBQcA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> >> >> -- >> 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/ab8b9168-9459-476b-9b9b-930c6763289a%40gmail.com >> <https://groups.google.com/d/msgid/everything-list/ab8b9168-9459-476b-9b9b-930c6763289a%40gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- > 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/CAMW2kAp7UGDVrCzGRnrucy%3DzYRUgOM0-o1X7Vhs1j6c5GVQygg%40mail.gmail.com > <https://groups.google.com/d/msgid/everything-list/CAMW2kAp7UGDVrCzGRnrucy%3DzYRUgOM0-o1X7Vhs1j6c5GVQygg%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > > > -- > 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/23bf8e7f-645e-4f5e-a056-b3fc200a958c%40gmail.com > <https://groups.google.com/d/msgid/everything-list/23bf8e7f-645e-4f5e-a056-b3fc200a958c%40gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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