> Il 3 maggio 2018 alle 16.28 Bruno Marchal <marc...@ulb.ac.be> ha scritto: > > > > > > On 1 May 2018, at 18:13, 'scerir' via Everything List < > everything-list@googlegroups.com mailto:everything-list@googlegroups.com > > wrote: > > > > > > > > > > > > > Il 1 maggio 2018 alle 17.36 Bruno Marchal < > > marc...@ulb.ac.be mailto:marc...@ulb.ac.be > ha scritto: > > > > > > > > > > > > > > > > On 29 Apr 2018, at 08:21, > > > 'scerir' via Everything List < everything-list@googlegroups.com > > > mailto:everything-list@googlegroups.com > wrote: > > > > > > > > > > > > IMO Schroedinger invented this manyworlds or manyminds > > > > or manywords interpretation. > > > > > > > > > > > > > > The quote below seems to indicate that this is not the case, > > > unless you agree (with me, and Deutsch, …) that QM *is* the discovery of > > > the many superposed worlds/states/minds, and that the founder added the > > > collapse postulate ONLY to avoid the proliferation of the alternate > > > worlds/states/minds. > > > > > > > > > > Yes, I can agree with that. But it is possible there was, in those > > years, another issue too. I mean conservation of energy. It is not > > possible, in general, to preserve conservation of energy in each universe > > during the split-decoherence, especially in case of superposition of states > > of different energy. In this special case energy increase in one universe > > and decrease in another universe. > > > > > > The conservation of energy seems to me to be a classical, and mainly > statistical notion. I do not see why the many-universes would violate > thermodynamics in any branches, given that, by linearity of evolution, each > branch evolves independently of the others, and the branches can only > interfere, statistically, from the first person perspective of the observer. > I am not even sure how we could superpose two states with different energy. > May be you could explain me this. > > Bruno >
The worlds are not autonomous during the split (decoherence process) of the original unique world. "Now, there isn't really a story to tell about what the total energy in individual universes is during that whole process [of measurement]. Because the universes are not autonomous during it. But one thing's for sure, there is no way of construing it so that the energy in each particular universe is conserved, for the simple reason that the whole system starts out the same on each run of the experiment (before the non-sharp state is created), and ends up different". --David Deutsch In a superposition of states of different energy I am inclined to think (naively) that the energy of the superposition state lies in between the energy of its constituents. Actually the theory only states there are expectation values, that is to say what you get if you perform many measurements, and then you average. Now the measurement process itself is an "interaction" with the superposition state, and I do not know whether this interaction, in the MWI, is unitary or not. "In more general cases, where there are superpositions of states of different energy, energy can increase in one universe at the cost of decreasing in another." --David Deutsch But let us read Hartle here https://arxiv.org/abs/gr-qc/9410006 http://blog.jessriedel.com/2015/08/23/how-to-think-about-quantum-mechanics-part-6-energy-conservation-and-wavefunction-branches/ . > > > > > > > > > > > Everett is just the guy who realise that the > > MW does not leads to a jelly quagmire of everything, by taking the first > > person view (what he called subjective) of the observers, as their memories > > get as much quasi orthogonal that the results they could have attributed to > > a collapse. The collapse, and the irreversibility is purely “subjective” > > (first person) and irreversible in principle for *us*. To reverse the > > entire universal wave, we would need to go outside the physical universe in > > some practical way, which, needless to say, is rather difficult. > > > > > > But I do agree with you, Schroedinger and Einstein understood > > > that the collapse was a problem for the rest of physics and philosophy. > > > They were rightly skeptical that Bohr and Heisenberg got the whole thing. > > > Would have they like Everett? Bohr just threw Everett out of his home, I > > > have read somewhere. I think Einstein would have prefer it to anything > > > involving an action at a distance, like Bohm’s theory (non local hidden > > > variable theory). Indeed, as you all know, Einstein told that he would > > > have prefered to be a plumber than be involved in a theory with some > > > action-at-a distance. > > > > > > Bruno > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Il 28 aprile 2018 alle 23.01 > > > > agrayson2...@gmail.com mailto:agrayson2...@gmail.com ha scritto: > > > > > > > > > > > > > > > > > > > > On Saturday, April 28, 2018 at 5:55:16 AM UTC, > > > > > scerir wrote: > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I think Schroedinger and > > > > > > his cat bear some responsibility. In trying to debunk Born's > > > > > > probabilistic interpretation he appealed to the absurdity of > > > > > > observation changing the physical state...even though no one had > > > > > > actually proposed that. > > > > > > > > > > > > > > Brent > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > “The idea that the alternate measurement > > > > > > outcomes be not alternatives but all really happening > > > > > > simultaneously seems lunatic to the quantum theorist, just > > > > > > impossible. He thinks that if the laws of nature took this form > > > > > > for, let me say, a quarter of an hour, we should find our > > > > > > surroundings rapidly turning into a quagmire, a sort of a > > > > > > featureless jelly or plasma, all contours becoming blurred, we > > > > > > ourselves probably becoming jelly fish. It is strange that he > > > > > > should believe this. For I understand he grants that unobserved > > > > > > nature does behave this way – namely according to the wave > > > > > > equation. . . . according to the quantum theorist, nature is > > > > > > prevented from rapid jellification only by our perceiving or > > > > > > observing it.” > > > > > > > > > > > > -Erwin Schroedinger, The Interpretation of > > > > > > Quantum Mechanics. Dublin Seminars (1949-1955) and Other > > > > > > Unpublished Assays (Ox Bow Press, Woodbridge, Connecticut, 1995). > > > > > > > > > > > > > > > > > > > > > > Who is Schrodinger referring to? This was written > > > > > before 1957, when Everett published his MWI.? Were other theorists > > > > > advancing the idea that all alternatives are physically manifested in > > > > > reality? AG > > > > > > > > > > > > > > > > > > > > -- > > > > > 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 > > > > > everything-list+unsubscr...@googlegroups.com > > > > > mailto:everything-list+unsubscr...@googlegroups.com . > > > > > To post to this group, send email to > > > > > everything-list@googlegroups.com > > > > > mailto:everything-list@googlegroups.com . > > > > > Visit this group at > > > > > https://groups.google.com/group/everything-list. > > > > > For more options, visit > > > > > 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 > > > > everything-list+unsubscr...@googlegroups.com > > > > mailto:everything-list+unsubscr...@googlegroups.com . > > > > To post to this group, send email to > > > > everything-list@googlegroups.com > > > > mailto:everything-list@googlegroups.com . > > > > Visit this group at > > > > https://groups.google.com/group/everything-list. > > > > For more options, visit > > > > 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 everything-list+unsubscr...@googlegroups.com > > > mailto:everything-list+unsubscr...@googlegroups.com . > > > To post to this group, send email to > > > everything-list@googlegroups.com mailto:everything-list@googlegroups.com . > > > Visit this group at > > > https://groups.google.com/group/everything-list. > > > For more options, visit 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 everything-list+unsubscr...@googlegroups.com > > mailto:everything-list+unsubscr...@googlegroups.com . > > To post to this group, send email to > > everything-list@googlegroups.com mailto:everything-list@googlegroups.com . > > Visit this group at https://groups.google.com/group/everything-list. > > For more options, visit 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 everything-list+unsubscr...@googlegroups.com > mailto:everything-list+unsubscr...@googlegroups.com . > To post to this group, send email to everything-list@googlegroups.com > mailto:everything-list@googlegroups.com . > Visit this group at https://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Everything List" group. 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