On Tuesday, December 25, 2018 at 1:16:53 PM UTC, John Clark wrote: > > On Mon, Dec 24, 2018 at 3:21 PM <[email protected] <javascript:>> wrote: > > >> You can never prove that any physical quantity is exactly zero, but we >>> do know from observations of the cosmic microwave background radiation that >>> if the universe is curved at all it is by less than one part in 100,000. >>> >> > > *> Agreed. However, IMO the observed universe cannot be flat with exactly >> zero curvature (which I refer to as "mathematically flat) since that would >> imply infinite volume * >> > > If information can't travel faster than light then by definition the > radius of the spherical volume of the universe you can observe can't be > larger than the age of the universe in years times a light year. > > >> *> **which contradicts its finite age.* >> > > There is no reason spacetime couldn't extend a finite distance into the > past but an infinite distance into the future. >
*The observable universe could continue to expand forever, but it always has a finite radius. We have no information about the unobserved part, so it could be any size, maybe even tiny. AG* > > John K Clark > > -- 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 post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
