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] > <javascript:>> 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* >> > > 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] <javascript:>. >> 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/a31f806e-0b3c-4bc3-a6d9-5b1543f11918%40googlegroups.com.
