On Sun, Sep 15, 2024 at 8:24 AM John Clark <[email protected]> wrote:
> On Sun, Sep 15, 2024 at 3:26 AM Alan Grayson <[email protected]> > wrote: > > > *I prefer approximately spherical compared to flat because as we go >> backward in time, we can enclose the universe in a sphere, implying it >> is finite in spatial extent (not infinite).* > > > *There is no such implication. If the universe is a 3-sphere then it could > be finite or infinite. A 3-sphere is a compact, connected, 3-dimensional > manifold without boundary embedded in 4-space, any loop on a 3-sphere can > be continuously shrunk to a point without leaving the 3-sphere.* > https://math.stackexchange.com/questions/2990455/do-all-compact-manifolds-have-finite-volume seems to be saying that compactness implies finite volume. Jesse > > * > It then occurred to me that the Unobservable universe was plausibly >> created during Inflation, * > > > *NO. The rate of expansion during inflation was mind blowingly gargantuan, > but it was finite. If the universe was infinite before inflation then it > was infinite after it, and if it was finite before inflation then it was > finite after it. * > > *> to Alan Guth. I asked him, when he assumes the universe was around the >> size of a proton when Inflation began, was he referring only to the >> Observable universe,* > > > *I know for a fact Guth was referring to the observable universe because > he's a good enough physicist to know that a proton and the observable > universe have one thing in common, both of them are finite in size. And no > physical process can turn a finite thing into an infinite thing. * > > * > or both hypothetic parts, Observable and Unobservable. * > > > *If the universe has any curvature at the largest possible scale it is > unobservable, and if you insist that postulating that something you cannot > observe and will never be able to observe nevertheless exists is > unscientific, then you would have to conclude that the pope was right and > Galileo was wrong because the Earth really is the center of the universe. > Do you really want to insist on that? * > John K Clark See what's on my new list at Extropolis > <https://groups.google.com/g/extropolis> > > uss > > > >> -- > 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/CAJPayv3hPmd-V4p9a93iN_Q%3D4Q4NDhsdxcOkvEGGghMQ0w0YVw%40mail.gmail.com > <https://groups.google.com/d/msgid/everything-list/CAJPayv3hPmd-V4p9a93iN_Q%3D4Q4NDhsdxcOkvEGGghMQ0w0YVw%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- 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/CAPCWU3KUD4aLqNe7XSR%2B9QJ5GDuDYtroUNrdOhEoCjevdX2ctA%40mail.gmail.com.
