On Saturday, January 25, 2025 at 9:27:58 PM UTC-7 Brent Meeker wrote: On 1/25/2025 6:56 PM, Alan Grayson wrote:
*Yes. I don't think I ever made a theoretical argument; just an empirical one that the universe was never spatially infinite, now or in the past. * There's no empirical argument for that because the universe looks flat, which is empirically consistent with it being spatially infinite. Now you may object to that on some philosophical or metaphysical grounds and just say it is very, very big compared to the part we can see and hence looks flat (as the Earth looks flat locally). *Cosmologists agree that the universe gets smaller as we go backward in time. How could it get smaller as it returns to the BB, and yet still be infinite in spatial extent? * It could have been always spacially infinite. *Sure, but I'm arguing that it couldn't BECOME spatially infinite in finite time, regardless of its rate of expansion. So if it is now spatially infinite, that must have been its initial condition. But I reject that conjecture on the grounds that it's a type of singularity, and we strrongly tend to reject theories which posits a singularity. AG* Brent *Much more plausible is that it was never infinite in spatial extent. If GR assumes an infinite universe at T=0, on what principle was that assumed? Off hand it seems gratuitous. 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 everything-list+unsubscr...@googlegroups.com. To view this discussion visit https://groups.google.com/d/msgid/everything-list/9aaf9e50-d3c3-4ba0-918d-430294cf41b3n%40googlegroups.com.
