On Saturday, September 14, 2019 at 1:55:36 AM UTC-6, Alan Grayson wrote: > > > > On Saturday, September 14, 2019 at 12:34:18 AM UTC-6, Jason wrote: >> >> >> >> On Friday, September 13, 2019, Alan Grayson <[email protected]> wrote: >> >>> >>> >>> On Friday, September 13, 2019 at 4:42:00 PM UTC-6, Jason wrote: >>>> >>>> >>>> >>>> On Fri, Sep 13, 2019 at 8:25 AM Alan Grayson <[email protected]> >>>> wrote: >>>> >>>>> >>>>> >>>>> On Friday, September 13, 2019 at 5:24:11 AM UTC-6, Bruno Marchal wrote: >>>>>> >>>>>> >>>>>> On 13 Sep 2019, at 04:26, Alan Grayson <[email protected]> wrote: >>>>>> >>>>>> >>>>>> >>>>>> On Thursday, September 12, 2019 at 11:01:54 AM UTC-6, Alan Grayson >>>>>> wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Thursday, September 12, 2019 at 7:45:22 AM UTC-6, Lawrence >>>>>>> Crowell wrote: >>>>>>>> >>>>>>>> On Thursday, September 12, 2019 at 4:20:46 AM UTC-5, Philip Thrift >>>>>>>> wrote: >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> On Wednesday, September 11, 2019 at 11:45:41 PM UTC-5, Alan >>>>>>>>> Grayson wrote: >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> https://www.wired.com/story/sean-carroll-thinks-we-all-exist-on-multiple-worlds/ >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> Many Worlds is where people go to escape from one world of >>>>>>>>> quantum-stochastic processes. They are like vampires, but instead of >>>>>>>>> running away from sunbeams, are running away from probabilities. >>>>>>>>> >>>>>>>>> @philipthrift >>>>>>>>> >>>>>>>> >>>>>>>> This assessment is not entirely fair. Carroll and Sebens have a >>>>>>>> paper on how supposedly the Born rule can be derived from MWI I have >>>>>>>> yet >>>>>>>> to read their paper, but given the newsiness of this I might get to >>>>>>>> it. One >>>>>>>> advantage that MWI does have is that it splits the world as a sort of >>>>>>>> quantum frame dragging that is nonlocal. This nonlocal property might >>>>>>>> be >>>>>>>> useful for working with quantum gravity, >>>>>>>> >>>>>>>> I worked a proof of a theorem, which may not be complete >>>>>>>> unfortunately, where the two sets of quantum interpretations that >>>>>>>> are ψ-epistemic and those that are ψ-ontological are not decidable. >>>>>>>> There >>>>>>>> is no decision procedure which can prove QM holds either way. The >>>>>>>> proof is >>>>>>>> set with nonlocal hidden variables over the projective rays of the >>>>>>>> state >>>>>>>> space. In effect there is an uncertainty in whether the hidden >>>>>>>> variables >>>>>>>> localize extant quantities, say with ψ-ontology, or whether this >>>>>>>> localization is the generation of information in a local context from >>>>>>>> quantum nonlocality that is not extant, such as with ψ-epistemology. >>>>>>>> Quantum interprertations are then auxiliary physical axioms or >>>>>>>> postulates. >>>>>>>> MWI and within the framework of what Carrol and Sebens has done this >>>>>>>> is a >>>>>>>> ψ-ontology, and this defines the Born rule. If I am right the >>>>>>>> degree of ψ-epistemontic nature is mixed. So the intriguing >>>>>>>> question we can address is the nature of the Born rule and its tie >>>>>>>> into the >>>>>>>> auxiliary postulates of quantum interpretations. Can a similar >>>>>>>> demonstration be made for the Born rule within QuBism, which is what >>>>>>>> might >>>>>>>> be called the dialectic opposite of MWI? >>>>>>>> >>>>>>>> To take MWI as something literal, as opposed to maybe a working >>>>>>>> system to understand QM foundations, is maybe taking things too far. >>>>>>>> However, it is a part of some open questions concerning the >>>>>>>> fundamentals of >>>>>>>> QM. If MWI, and more generally postulates of quantum >>>>>>>> interpretations, are connected to the Born rule it makes for some >>>>>>>> interesting things to think about. >>>>>>>> >>>>>>>> LC >>>>>>>> >>>>>>> >>>>>>> If you read the link, it's pretty obvious that Carroll believes the >>>>>>> many worlds of the MWI, literally exist. AG >>>>>>> >>>>>> >>>>>> Carroll also believes that IF the universe is infinite, then there >>>>>> must exist exact copies of universes and ourselves. This is frequently >>>>>> claimed by the MWI true believers, but never, AFAICT, proven, or even >>>>>> plausibly argued. >>>>>> >>>>>> >>>>>> The idea comes from Tegmark, and I agree with you, it necessitate >>>>>> more than an infinite universe. It requires also some assumption of >>>>>> homogeneity. >>>>>> >>>>> >>>>> Our universe is, on a large scale, homogeneous. But it can't be >>>>> infinite since it has only been expanding for finite time, 13.8 BY. I had >>>>> a >>>>> discussion with Brent about this some time ago, and he claimed finite in >>>>> time doesn't preclude infinite in space. I strongly disagree. Perhaps I >>>>> am >>>>> missing something. Wouldn't be the first time. AG >>>>> >>>> >>>> I think what you may be missing is that in popular (but misleading) >>>> accounts of the BB they often say everything originated from a point, >>>> rather than everywhere at once. To say "everything came from a point" is >>>> at best only valid for describing the observable universe (or any finite >>>> portion of the universe) but is invalid to extrapolate it to the whole >>>> universe, which may be spatially infinite. >>>> >>> >>> I am not assuming our universe began from a mathematical point, but I do >>> assume that 13.8 BYA it was very very small, the observable and >>> unobservable parts. >>> >> >> Why do you assume this? Most cosmologists make no such assumption. >> Under the concordance (standard assumed) model of cosmology, space is >> infinite. >> >> >>> >>> >>> >>> I don't think there is an implied disconnect between our measurements >>> of the CMBR and what an observer would measure in parts we have no access >>> to. It was everywhere hot and dense, and very very small. >>> >> >> There's no observational motivation for the universe being very very >> small at the beginning. It could have been small, large or infinite, for >> all we know. >> >> >>> If it were infinite at that time, its temperature would have been near >>> absolute zero. AG >>> >> >> I think you're working under the assumption that some finite amount of >> energy was injected into space at one particular point. This is not what >> the big bang theory says, rather all space (everywhere there was space), >> was equally hot and dense. >> >> Inflation modifies the picture a bit where the vacuum of space expands >> rapidly due to its high energy density (which suggests a negative >> pressure). Under the equations of GR, such a state would expand itself >> exponentially. Eventually parts of this vacuum decay to a lower energy >> density, and this dump of energy into space gives us the early hot stage of >> the big bang. >> >> We don't know how big this initial inflating space was, but if inflation >> is right, most of the universe is still experiencing exponential growth. >> > We don't know why inflation started and what stopped it, if it stopped. AG
> >> Each pocket universe may be finite in volume, but extends infinitely in >> the time direction. >> > > Yes, time extends infinitely into the future, and so does space, *unless > the universe is closed.* But then he claims time and space flip when > viewed externally to the bubble. But how does one get outside the bubble to > observe it? Not possible AFAICT. AG > > >> As Alan Guth explains, GR can warp things in the internal view of each >> pocket universe such that the time and space dimensions flip, the infinite >> time dimension within the pocket universe can give rise to the appearance >> of infinite space, and the finite space appears as finite time: >> >> https://youtu.be/rfeJhzPq3jQ >> >> Jason >> > -- 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 on the web visit https://groups.google.com/d/msgid/everything-list/c70cefbd-d0ff-43df-9b4e-4d125a56a306%40googlegroups.com.
