> On 8 Aug 2018, at 13:50, Bruce Kellett <[email protected]> wrote: > > From: Bruno Marchal <[email protected] <mailto:[email protected]>> >>> On 8 Aug 2018, at 01:39, Bruce Kellett <[email protected] >>> <mailto:[email protected]>> wrote: >>> >>> From: Bruno Marchal <[email protected] <mailto:[email protected]>> >>>> >>>> If there is a FTL physical influence, even if there is no information >>>> transfer possible, it leads to big problems with any reality >>>> interpretation of special relativity, notably well described by Maudlin. >>>> Maudlin agrees that many-mind restore locality, and its “many-mind” theory >>>> is close to what I think Everett had in mind, and is close to what I >>>> defended already from the mechanist hypothesis. To be sure, Albert and >>>> Lower Many-Minds assumes an infinity of mind for one body, where in >>>> mechanism we got an infinity of relative body for one mind, but the key >>>> issue is that all measurement outcomes belongs to some mind. The >>>> measurement splits locally the observers, and propagate at subliminal >>>> speed. >>> >>> I don't think that the many-minds interpretation is really what you would >>> want to support. In many-minds, the physical body is always in the >>> superposition of all possible results, but the 'mind' can never be in such >>> a superposition, >> >> That sides with Mechanism. In arithmetic there is an infinity of identical >> (at the relevant representation level) brains. Now Albert and Loewer seems >> to associate an infinity of mind with one body. > > The 'infinity of minds for each body' was postulated by Albert and Lowe to > avoid the 'mindless hulk' problem. In other words, it was just an ad hoc fix > for a problem in the theory. This alone should have been sufficient to render > the theory unacceptable.
I agree. That is why I remain closer to Everett. This problem is automatically solved with Mechanism. There is no empty hulk, given that there is no hulk. > >> I do not understand this, and with the Mechanist “many-dreams” it is the >> contrary: each mind as an infinity of (virtual) bodies, and the >> consciousness will differentiate along their computational different >> continuations. Take the WM-duplication. After the reconstitution, but before >> the copies open the door, one mind is associated to two bodies, and then >> differentiates in W or in M from each location perspective. To say that the >> mind is not in a superposition is equivalent with Everett’s justification >> that the observer cannot feel the split, and it is where Everett use (more >> or less explicitly) the mechanist hypothesis. > > The splitting in Everett's theory at least makes some sort of sense, and is > not postulated ad hoc. I agree. > The real problem I see with many-minds theory is that it does not actually > explain the observed correlations. The correlations are presumed not to exist > in reality -- all possible combinations of experimental outcomes happen, but > when Alice and Bob meet, their bodies are still in indefinite states -- no > actual results are recorded by entanglement with their bodies -- but their > minds will be in definite states that agree with the quantum correlations. > This step seems to introduce yet more unreasonable magic into the > 'explanation'. Why are the minds like this when they communicate? Because all Alice and Bob are coupled in that way, by the singlet state. That works if we keep in mind that the singlet state (when not already observed by neither Alice nor Bob) describes an infinity of Alice and Bob, with the spin in all directions, but always correlated. When Alice and Bob make their measurement, if they are space separated, it makes no sense to ask if they are or not in the same world or branches. The result they obtained only entangle each of them with the environment, locally, and that spread on the whole universe (at subliminal speed) so that both of them will encounter only their “correlated” counterparts. > Especially since there are pairs of observers who get results that do not > agree with QM (the 'mindless hulks!’). Alice and Bob always get results which confirms QM. But when they are space-like separated, their consciousness will only be able to differentiate into histories which contains the correlation. > > Maudlin moved on in the years between the first edition of his book in 1994 > and the third edition in 2011. You told me. Maudlin is very good, but is not a fan of Everett, nor even of Mechanism. He argued also, and independently of me, that it makes no sense to keep both mechanism and materialism. The end of his paper “Computation and Consciousness” (Journal of Philosophy, 1989) suggests he is more willing to keep Materialism instead of Mechanism. I show that indeed the mechanist solution generalises Everett on the whole (sigma_1, semicomputable) part of the arithmetical reality/truth. I reduce the mind-body problem to the problem of recovering physics from a statistics on first person experience in arithmetic (where there is no hulk, nor need of hulk). > In his 2011 thinking I can only imagine that he would have seen many-minds in > much the same way as he later saw many-worlds -- if appeal is made to the > wave function to make sense of the correlations in many-worlds, then we have > to recognize that this is not a local account since the wave function is not > a local object. I don’t really understand what you mean by that. I am reading your paper, which is nice and well written, but too quick for me on both Tipler and Baylock. It helps me to better see how you interpret the wave, and where we might differ. It seems to me that when Alice and Bob prepare the singlet state, even before their long distance separation, there is no sense to say that they are still in the same world. They are only because their interact and entangle and re-entangle very quickly, but still always at light speed or slower. But even if there is only one cm between Alice and Bob, it makes no sense to say that they are in the same world. They might find uncorrelated results, but, at the speed of alight, each one will only be able to talk to its correctly correlated counterparts. > The same can clearly be said of the many-minds approach. > > The wave function is not local because the entangled singlet state is > non-separable. OK. > Non-separability means that if you interact with one part of the state, you > affect the whole state: I am not sure you affect any state. You just discover in which branch you are. The wave only described a multiplicity of realties(available history), and in this case, when someone, Alice say, look at something inseparable, she got information about her branche(s), and of course she knows that any possible future Bob will have the correlated result. But Bob, if space-separated, might very well find a non correlated result, which means that he localised itself in another branch, where him too will only be able to meet his corresponding correctly correlated Alice. That is how I interpret the QM wave, or the Heisenberg matrices. I am afraid that a “real” treatment would need a quantum theory of space itself, but this needs a solution to the quantum gravity problem. > the state cannot be split into separate non-interacting parts, one for each > particle in the singlet. I agree with this. But that can be interpreted by the fact that we are ignorant in which branch we are. Being in the same branch is an equivalence relation on the object with which we can interact with, and space separation entails that the measurement are truly uncorrelated “in the absolute”, yet all the Alices and Bobs couples localises themselves in the branches violating the Bell’s inequality. Alice would need to go quicker than the speed of light to see some Bob finding an uncorrelated result, like overpassing the decoherence time. > That is why the non-locality is unavoidable -- in many minds as in > many-worlds -- it is an intrinsic part of quantum theory, and is perhaps the > most significant way in which quantum mechanics differs from classical > mechanics (you don't get non-separable states in classical mechanics, > although you do get interference between classical waves). I agree with all this, but the many-worlds, or the relative states explains this without a physical action acting FTL. It is very special indeed, as the confirmation of that Bell’s Inequality violation confirms that LOCALITY + DETERMINACY (+ some amount of physical realism) makes the Relative States existence obligatory. Which of course I find nice, as it makes QM looking exactly like a solution of the Mechanist Mind-body problem, where the physical body can be shown to make sense only through a statistics on all computational states (structured by self-referential correctness). > >>> so stochastically chooses to record only one definite result from the mix. >>> In the Wikipedia article on the many-minds interpretation, the following >>> comment might be relevant for you: >>> >>> "Finally, [many-minds] supposes that there is some physical distinction >>> between a conscious observer and a non-conscious measuring device, so it >>> seems to require eliminating the strong Church–Turing hypothesis >>> <https://en.wikipedia.org/wiki/Church%E2%80%93Turing_thesis#Philosophical_implications> >>> or postulating a physical model for consciousness.” >> >> >> What does they mean by “Strong Church-Turing hypothesis”? > > I imagine that the Wikipedia author means that the strong CT hypothesis > supposes that the world is nothing more than a computation. STRONG CT would be Digital Physicalism. This has been refuted since long, if by world we mean the physical world. If my local body is Turing emulable (with consciousness preservation), then physics is reduced to a statistics on all computations, which can be shown to have non computable elements. The physical reality can be very well approximated by a computation, but in the limit (where the first person lives) it cannot be computable. To make some measurement and get all correct decimal in a theory for that measurement, you need to execute the whole universal dovetailing in an instant, which is impossible. Mechanism makes also matter trivially not clonable. You cannot clone your infinite ignorance about which computations execute you. > >> The above sentence does not make sense. The many-worlds theory is a direct >> consequence of the SWE + the mechanist theory theory of mind. It is the >> collapse of the wave which would be threat to Mechanism (and of >> Rationalism). >> >> >> >>> >>> If machines can do something that the mind cannot do (viz., be in a >>> superposition of all possible results, when the mind cannot participate in >>> any such superposition), >> >> The mind cannot NOT participate to the infinite superposition which is not >> eliminable from arithmetic. That is why we have an infinity of body in >> arithmetic, and why when we look closely to the environment, i.e. below our >> mechanist substitution level, we must find the sign of the presence of the >> alternate computations, like QM-without-collapse confirmed. > > So, contrary to what you said above, you do not really agree that the > supposedly local 'many-minds' account given by Maudlin in his book is close > to what you think? You can say that. Maudlin saw that the Many-Mind theory is local (at least in his 2009 book, I will buy the 2011 soon or later) but he surimposed a “one world” structure, which leads to empty hulk and zombie and to an infinity of mind for one body, which makes not much sense. I think all this comes from too much naive notion of mind and world. With computationalism we get the opposite: each mind get associated with an infinity of relative computational states, the different modes (true, believable, knowable, observable, sensible) result from the incompleteness of all universal theories. > >>> the Church-Turing thesis goes out the window -- and you might not want to >>> say "Yes, Doctor". >> >> I think the complete opposite of this is correct. Church’s thesis go hand in >> hand with the non collapse (and non guiding potential) of the quantum wave. >> The only problem that Everett missed, is that, for all this to be >> consistent, extract the formalism of the Wave itself from the statistic on >> all computations. Then the logic of machine self-reference and its variants >> imposed by incompleteness gives the complete solution at the propositional >> level, and that works, in the sense that we get quantum logic where we >> should, making Mechanism not (yet) refuted by observations. > > But that is your theory of mechanism, which is not to be found in quantum > theory at all. Everett use Mechanism. Darwin uses Mechanism. Diderot defined rationalism by Mechanism, and when Milinda ask to Arjuna what Arjuna is, Arjuna explained what a machine is. It is not my theory of Mechanism. It is a very old idea. Then Incompleteness, which is a one-diagonalization consequence of the Church-Turing, shows that we are quite ignorant of what machine can and cannot do, and the execution of all computations in arithmetic invites us by itself to doubt physicalism. There is a non physical reason for the physical laws: they emerge from the logic of what the average universal machine (an arithmetical notion) can bet to live from its first person perspective. There is a many-dreams interpretation of arithmetic/combinator, and all universal number/combinator converges to it. And if that differ from the observations, it will be time to invoke magical things like primary matter or spooky action at a distance, or elves and gods and other actual infinities. But then I need strong evidence, and a departure of Nature from the machine’s observable mode might be such. But up to now, nature seems to obey the laws of the universal machine dreams. Bruno > > 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] > <mailto:[email protected]>. > To post to this group, send email to [email protected] > <mailto:[email protected]>. > Visit this group at https://groups.google.com/group/everything-list > <https://groups.google.com/group/everything-list>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
