On Monday, January 13, 2020 at 2:54:48 AM UTC-7, Quentin Anciaux wrote: > > > > Le lun. 13 janv. 2020 à 10:50, Alan Grayson <[email protected] > <javascript:>> a écrit : > >> >> >> On Monday, January 13, 2020 at 2:38:57 AM UTC-7, Quentin Anciaux wrote: >>> >>> >>> >>> Le lun. 13 janv. 2020 à 10:28, Alan Grayson <[email protected]> a >>> écrit : >>> >>>> >>>> >>>> On Monday, January 13, 2020 at 1:33:01 AM UTC-7, stathisp wrote: >>>>> >>>>> >>>>> >>>>> On Mon, 13 Jan 2020 at 13:48, Alan Grayson <[email protected]> >>>>> wrote: >>>>> >>>>>> >>>>>> >>>>>> On Sunday, January 12, 2020 at 8:58:06 AM UTC-7, John Clark wrote: >>>>>>> >>>>>>> On Thu, Jan 2, 2020 at 2:30 AM Alan Grayson <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>> >>>>>>>> *> If we're convinced it's finite in age, then it can't be infinite >>>>>>>> in spatial extent. AG * >>>>>>> >>>>>>> >>>>>>> We don't know for sure our universe is infinite in size and we'll >>>>>>> never know for sure because we'll never be able to measure precisely >>>>>>> zero >>>>>>> curvature with no error at all, but we do know it's pretty damn flat, >>>>>>> if >>>>>>> it's curved it's so slight that a light beam would have to go at least >>>>>>> 500 >>>>>>> times as far as our telescopes can see for it to return where it >>>>>>> started. >>>>>>> So if you respect the empirical evidence for the Big Bang but the idea >>>>>>> of a >>>>>>> beginning of a infinitely sized universe makes you unhappy then the >>>>>>> Multiverse idea offers you an obvious solution, you get an infinitely >>>>>>> large >>>>>>> infinitely old Multiverse but with the observable universe having a >>>>>>> beginning and being only finitely large. However I understand the >>>>>>> Multiverse makes you unhappy too. I fear you may be destined to be >>>>>>> unhappy. >>>>>>> >>>>>>> By the way ... does the inverse also make you unhappy, something >>>>>>> infinitely old but finite in spatial extent? >>>>>>> >>>>>>> John K Clark >>>>>>> >>>>>> >>>>>> *All the models pictorially represented, have the Universe beginning >>>>>> very small, and inflation is claimed to increase its size from, say, >>>>>> much >>>>>> smaller than a proton, to about the size of the Earth or Solar System in >>>>>> a >>>>>> few Planck intervals. If it begins small, or if you run the clock >>>>>> backward >>>>>> it becomes progressively smaller, how could it have started with >>>>>> infinite >>>>>> spatial extent? Don't you see something wrong with the model? AG* >>>>>> >>>>> >>>>> The model says that a subset of the universe starts small and gets >>>>> bigger. This is not inconsistent with the whole universe starting and >>>>> remaining infinite in spatial extent. >>>>> >>>>>> -- >>>>> Stathis Papaioannou >>>>> >>>> >>>> *I thought I made that clear; what I am calling "the universe" is >>>> precisely the SUBSET you refer to, which starts small and gets bigger. It >>>> is THAT SUBSET which cosmologists claim has infinite spatial extent, based >>>> on measurements. What you're calling "the whole universe" includes the >>>> underlying entity on which the BB started, and on which measurements >>>> CANNOT >>>> be made. It could be infinite in spatial extent, or is possibly an entity >>>> for which the concept of spatial extent might not exist. AG* >>>> >>> > And so what do you see not contradictory in the existence of the universe > itself ? Either it has always been, or not, and if not, that makes no > sense. I see nothing contradictory to have something infinite, so it could > always has been infinite in content, seeing it as zero volume is a mistake > because that presuppose a volume in another space. What I'm saying is that > there was infinite content (and still is) but all metrics (space) was of > zero extends, and inflation extended the "space" not the content. >
*I don't think you understand the issue I've raised; namely, if our bubble has a finite age and is expanding, it must be finite in spatial extent since the expansion rate is finite. But a flat universe, claimed by most, maybe all cosmologists, is infinite in spatial extent. How could it start infinite in spatial extent, yet be tiny in the beginning? I conclude that our universe, that is, our bubble (which doesn't include the substratum from which it arose), must be spherical and closed. AG* > > Anyway, in the end, there can't be an explanation which make sense. The > fact we're here in the first place being able to ask question is magical. > > Quentin > >> >>> As the bigbang is a singularity at the start... what prevents it to >>> contain an infinite content in a zero/small volume, after all it's a >>> singularity and we know only things after the big bang started ? and after >>> inflation (which I understand is only space metric which inflate), there is >>> still an infinite content. >>> >> >> *The BB is only a singularity as far as GR is concerned, because GR fails >> at that point in time. When we have a better theory, the alleged >> singularity at T = 0 will go away. What you call "infinite content in zero/ >> small volume" makes no sense, which is why we call this condition is called >> a singularity! How could the content be space, if you've have zero or small >> volume. This idea is immediately, and obviously, self contradictory. 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 [email protected]. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/everything-list/c9a07678-7721-4d68-ba7a-ea0b3455c4d7%40googlegroups.com >>>> >>>> <https://groups.google.com/d/msgid/everything-list/c9a07678-7721-4d68-ba7a-ea0b3455c4d7%40googlegroups.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> >>> >>> -- >>> All those moments will be lost in time, like tears in rain. (Roy >>> Batty/Rutger Hauer) >>> >> -- >> 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] <javascript:>. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/everything-list/a31f806e-0b3c-4bc3-a6d9-5b1543f11918%40googlegroups.com >> >> <https://groups.google.com/d/msgid/everything-list/a31f806e-0b3c-4bc3-a6d9-5b1543f11918%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > > > -- > All those moments will be lost in time, like tears in rain. (Roy > Batty/Rutger Hauer) > -- 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/692e04e2-eec2-4c8d-aca7-011087e41608%40googlegroups.com.
