On Friday, August 23, 2019 at 3:31:36 PM UTC-6, Lawrence Crowell wrote: > > On Thursday, August 22, 2019 at 12:37:40 AM UTC-5, Alan Grayson wrote: >> >> >> >> On Wednesday, August 21, 2019 at 7:12:14 PM UTC-6, Alan Grayson wrote: >>> >>> >>> >>> On Wednesday, August 21, 2019 at 3:13:11 PM UTC-6, Lawrence Crowell >>> wrote: >>>> >>>> On Tuesday, August 20, 2019 at 4:56:23 PM UTC-5, Alan Grayson wrote: >>>>> >>>>> https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology >>>>> >>>>> Is this a viable theory for avoiding a BB interpreted as a >>>>> singularity? AG >>>>> >>>> >>>> Penrose proposed a conformal identification of spatial infinity in the >>>> past and future i^±∞ of FLRW spacetimes. A cosmology expands and in the >>>> limit time → ∞ it transitions into a new cosmology. The de Sitter vacuum >>>> is >>>> not eternally stable, so the idea may have some germ of relevancy. I am >>>> not >>>> sure about how this would work with vacuum to vacuum transitions. The >>>> exponential expansion of the universe is a sort of time dependent >>>> conformal >>>> transformation with a small vacuum expectation for the scale field. To >>>> transition to a new cosmology, say with inflationary expansion, this means >>>> the vacuum expectation is increased. >>>> >>>> The overall physics community response to this has been tepid at best. >>>> There are some possible conflicts with observed data. >>>> >>>> LC >>>> >>> >>> FWIW, ISTM that what GR might be indicating about the BB, is that, >>> insofar as it's a singularity, it couldn't have occurred, and didn't >>> occur. This is to say the universe didn't become infinitely small in >>> spatial extent, like a mathematical point, but rather that there was a >>> maximal finite value of its energy density, hugely high but not infinite. >>> For this reason I find the cyclic models promising, although, as you >>> rightly indicate, they're far from complete or bug-free. AG >>> >> >> Which brings up a possibly relevant question: If the total energy of the >> universe occupied zero spatial volume (the presumed condition of the >> universe at t=o according to the BB theory), wouldn't that contradict the >> Uncertainty Principle? AG >> > > The total mass-energy content of the universe is zero. > > LC >
Is that a provable fact, or something that can be measured? TIA, 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/9d1307de-7f1b-4bcc-b124-f204bacc7873%40googlegroups.com.
