Bruno, Here is the snooker- from wiki MWI: ' Deutsch's derivation is a two-stage proof: first he shows that the number of orthonormal Everett-worlds after a branching is proportional to the conventional probability density. "

## Advertising

Who cares what the density of branching is- each branch is independent of all other branches and therefore all branches are equal. No way can probability enter into a single branch. Dreams are a result of many minds, not many worlds. Richard On Mon, Oct 29, 2012 at 12:18 PM, Richard Ruquist <yann...@gmail.com> wrote: > Bruno, > > I do not find Deutsch's introduction of a rational decision maker convincing > e.g.: http://arxiv.org/ftp/quant-ph/papers/9906/9906015.pdf > nor Wallaces elaboration on that theme > e.g.: http://arxiv.org/pdf/0906.2718v1.pdf. > > My belief is that a rational decision maker, somewhat like a god, > would following Leibniz, always chose the best quantum state in any > interaction > to become physical in a single universe. In fact that seems to be exactly what > Wallaces rational decision maker does. I think Deutsch has snookered us all. > Richard > > On Mon, Oct 29, 2012 at 11:28 AM, Bruno Marchal <marc...@ulb.ac.be> wrote: >> Hi Richard, >> >> On 28 Oct 2012, at 21:01, Richard Ruquist wrote: >> >>> Bruno, But it seems that the Gleason Theorem assigns probabilities to >>> the different universes in the multiverse that are not there in >>> Everett's MWI in the first place. Richard >> >> >> ? >> I don't see that, nor why you say so. can you elaborate? Gleason theorem >> just makes unique the usual Born rule, and justify a literal reading of the >> quantum amplitude as relative (infinite) proportions. >> It is quite similar to the Deutsch Hayden justification, in decision >> theoretical terms, of such amplitude reading, in the Heisenberg picture. >> >> Bruno >> >> >> >> >>> >>> On Sat, Oct 27, 2012 at 9:46 AM, Bruno Marchal <marc...@ulb.ac.be> wrote: >>>> >>>> >>>> On 26 Oct 2012, at 15:52, Richard Ruquist wrote: >>>> >>>>> Well Bruno, >>>>> >>>>> If the "measure problem" (which I take to be the assignment of >>>>> probabilities) is intrinsic to Everett's MWI, does that not amount to >>>>> negating it? >>>> >>>> >>>> >>>> Why? I think that it is beautifully solved by Gleason theorem, for the >>>> Hilbert space of dim bigger or equal to 3. >>>> >>>> >>>> >>>>> I did not suggest that it negated comp, which is what you >>>>> responded to. >>>> >>>> >>>> >>>> I think comp will confirms Everett QM, and this would make our sharable >>>> human or animal substitution level very plausibly at the Heisenberg >>>> uncertainty level, this for surviving even a long run, without detecting >>>> any >>>> difference. >>>> >>>> In that case, the Gleason solution will be the solution for comp. For >>>> this >>>> the X and Z logics (alreeady extracted) must conforms to some desiderata, >>>> already expressed by von Neumann, for a quantum logic, and which is that >>>> mainly it defines the searched measure. >>>> >>>> I m not sure I can understand string theory or any fundamental QM without >>>> Everett. >>>> >>>> I agree that the idea that we are multiplied by infinities at each >>>> instant >>>> is not attractive, but science is not wishful thinking, and besides, I >>>> don't >>>> take any theory too much seriously (we don't know). I also know that >>>> different theories can happen to be equivalent. >>>> >>>> Of course, to be sure, comp has also many attractive features, mainly its >>>> conceptual simplicity and naturalness. It really explains almost why >>>> there >>>> is something instead of nothing, as it assumes only 0 and the successor >>>> and >>>> the very simple laws, and explain from that how that very explanation >>>> emerges in some collection of stable numbers' dream. >>>> >>>> Bruno >>>> >>>> >>>> >>>> >>>> >>>> >>>>> Richard >>>>> >>>>> On Fri, Oct 26, 2012 at 9:35 AM, Bruno Marchal <marc...@ulb.ac.be> >>>>> wrote: >>>>>> >>>>>> >>>>>> Richard, >>>>>> >>>>>> On 25 Oct 2012, at 18:42, Richard Ruquist wrote: >>>>>> >>>>>>> Bruno, >>>>>>> >>>>>>> Doesn't the Gleason Theorem negate MWI by assigning probabilities? >>>>>>> Richard >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On the contrary. Gleason theorem solves the "measure problem" intrinsic >>>>>> in >>>>>> the Everett MWI, it makes the probabilities into comp (or weakening) >>>>>> first >>>>>> person indeterminacies. >>>>>> >>>>>> Unfortunately, comp necessitates a version of Gleason theorem for all >>>>>> comp >>>>>> states, not just the quantum one, as the quantum law must be derived >>>>>> from >>>>>> the 1p indeterminacies, occurring in arithmetic. >>>>>> >>>>>> The advantage is that comp provides the theory of both quanta and >>>>>> qualia >>>>>> (and a whole theology actually). >>>>>> Unfortunately, it is not yet clear if those quanta behave in a >>>>>> sufficiently >>>>>> quantum mechanical way, like making possible quantum computers, >>>>>> hydrogen, >>>>>> strings may be, etc. >>>>>> >>>>>> Bruno >>>>>> >>>>>> >>>>>> >>>>>> >>>>>>> >>>>>>> On Thu, Oct 25, 2012 at 9:38 AM, Bruno Marchal <marc...@ulb.ac.be> >>>>>>> wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 24 Oct 2012, at 19:53, meekerdb wrote: >>>>>>>> >>>>>>>> On 10/24/2012 4:31 AM, Bruno Marchal wrote: >>>>>>>> >>>>>>>> >>>>>>>> On 23 Oct 2012, at 14:50, Roger Clough wrote: >>>>>>>> >>>>>>>> Hi meekerdb >>>>>>>> >>>>>>>> There are a number of theories to explain the collapse of the quantum >>>>>>>> wave >>>>>>>> function >>>>>>>> (see below). >>>>>>>> >>>>>>>> 1) In subjective theories, the collapse is attributed >>>>>>>> to consciousness (presumably of the intent or decision to make >>>>>>>> a measurement). >>>>>>>> >>>>>>>> >>>>>>>> This leads to ... solipsism. See the work of Abner Shimony. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> 2) In objective or decoherence theories, some physical >>>>>>>> event (such as using a probe to make a measurement) >>>>>>>> in itself causes decoherence of the wave function. To me, >>>>>>>> this is the simplest and most sensible answer (Occam's Razor). >>>>>>>> >>>>>>>> >>>>>>>> This is inconsistent with quantum mechanics. It forces some devices >>>>>>>> into >>>>>>>> NOT >>>>>>>> obeying QM. >>>>>>>> >>>>>>>> >>>>>>>> No, it's only inconsistent with a reified interpretation of the wf. >>>>>>>> It's >>>>>>>> perfectly consistent with an instrumentalist interpretation. >>>>>>>> Decoherence >>>>>>>> is >>>>>>>> a prediction of QM in any interpretation. It's the einselection >>>>>>>> that's >>>>>>>> a >>>>>>>> problem. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> But instrumentalism is just an abandon of searching knowledge. There >>>>>>>> is >>>>>>>> no >>>>>>>> more what, only how. >>>>>>>> An instrumentalist will just not try to answer the question of >>>>>>>> betting >>>>>>>> if >>>>>>>> there is 0, 1, 2, ... omega, ... universes. >>>>>>>> >>>>>>>> And the einselection is not a problem at all, in QM + comp. It is >>>>>>>> implied. >>>>>>>> And, imo, the QM corresponding measure problem is solved by Gleason >>>>>>>> theorem >>>>>>>> (basically). >>>>>>>> >>>>>>>> And then, keeping that same 'everything' spirit, the whole QM is >>>>>>>> explained >>>>>>>> by comp. We have just to find the equivalent of "Gleason theorem" for >>>>>>>> the >>>>>>>> "material hypostases". >>>>>>>> >>>>>>>> Bruno >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> 3) There is also the many-worlds interpretation, in which collapse >>>>>>>> of the wave is avoided by creating an entire universe. >>>>>>>> This sounds like overkill to me. >>>>>>>> >>>>>>>> >>>>>>>> This is just the result of applying QM to the couple "observer + >>>>>>>> observed". >>>>>>>> It is the literal reading of QM. >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> So I vote for decoherence of the wave by a probe. >>>>>>>> >>>>>>>> >>>>>>>> You have to abandon QM, then, and not just QM, but comp too (which >>>>>>>> can >>>>>>>> only >>>>>>>> please you, I guess). >>>>>>>> >>>>>>>> Bruno >>>>>>>> >>>>>>>> >>>>>>>> http://iridia.ulb.ac.be/~marchal/ >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups >>>>>>>> "Everything List" group. >>>>>>>> To post to this group, send email to >>>>>>>> everything-list@googlegroups.com. >>>>>>>> To unsubscribe from this group, send email to >>>>>>>> everything-list+unsubscr...@googlegroups.com. >>>>>>>> For more options, visit this group at >>>>>>>> http://groups.google.com/group/everything-list?hl=en. >>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups >>>>>>> "Everything List" group. >>>>>>> To post to this group, send email to everything-list@googlegroups.com. >>>>>>> To unsubscribe from this group, send email to >>>>>>> everything-list+unsubscr...@googlegroups.com. >>>>>>> For more options, visit this group at >>>>>>> http://groups.google.com/group/everything-list?hl=en. >>>>>>> >>>>>> >>>>>> http://iridia.ulb.ac.be/~marchal/ >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups >>>>>> "Everything List" group. >>>>>> To post to this group, send email to everything-list@googlegroups.com. >>>>>> To unsubscribe from this group, send email to >>>>>> everything-list+unsubscr...@googlegroups.com. >>>>>> For more options, visit this group at >>>>>> http://groups.google.com/group/everything-list?hl=en. >>>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups >>>>> "Everything List" group. >>>>> To post to this group, send email to everything-list@googlegroups.com. >>>>> To unsubscribe from this group, send email to >>>>> everything-list+unsubscr...@googlegroups.com. >>>>> For more options, visit this group at >>>>> http://groups.google.com/group/everything-list?hl=en. >>>>> >>>> >>>> http://iridia.ulb.ac.be/~marchal/ >>>> >>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google Groups >>>> "Everything List" group. >>>> To post to this group, send email to everything-list@googlegroups.com. >>>> To unsubscribe from this group, send email to >>>> everything-list+unsubscr...@googlegroups.com. >>>> For more options, visit this group at >>>> http://groups.google.com/group/everything-list?hl=en. >>>> >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Everything List" group. >>> To post to this group, send email to everything-list@googlegroups.com. >>> To unsubscribe from this group, send email to >>> everything-list+unsubscr...@googlegroups.com. >>> For more options, visit this group at >>> http://groups.google.com/group/everything-list?hl=en. >>> >> >> http://iridia.ulb.ac.be/~marchal/ >> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To post to this group, send email to everything-list@googlegroups.com. >> To unsubscribe from this group, send email to >> everything-list+unsubscr...@googlegroups.com. >> For more options, visit this group at >> http://groups.google.com/group/everything-list?hl=en. >> -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.