On Saturday, September 14, 2019 at 7:29:33 AM UTC-6, Alan Grayson wrote: > > > > On Saturday, September 14, 2019 at 7:18:40 AM UTC-6, John Clark wrote: >> >> On Fri, Sep 13, 2019 at 11:22 PM Alan Grayson <[email protected]> >> wrote: >> >> *> What I think you're missing (and Tegmark) is the possibility of >>> UNcountable universes. In such case, one could imagine new universes coming >>> into existence forever and ever, without any repeats. Think of the number >>> of points between 0 and 1 on the real line, each point associated with a >>> different universe. AG* >>> >> >> There is no reason to think physics needs all the real numbers and >> considerable evidence to think it does not. To my mind the strongest >> evidence is that a physical Turing Machine is incapable of even >> approximating most real numbers, I happened to have posted a proof of this >> yesterday on the "Observation versus assumption" thread. >> > Physics doesn't need *all* the real numbers, just some of them, say any continuous range of any variable; like the mass of the electron. FWIW, I am convinced there are no exact copies of any universes or ourselves. AG
> >> Actually, physics might not even need all the rational numbers as there >> is probably a grainy structure to both space and time. Distances can't get >> smaller than the Planck Length and time shorter than the Planck Time. Maybe. >> >> >>> >> true regardless of if the Many Worlds Interpretation of Quantum >>>> Mechanics is correct or not, it only depends on the universe being >>>> spatially infinite. >>>> >>> >>> *> But our universe is NOT spatially infinite if its been expanding for >>> finite time,* >>> >> >> Sure it can, space could have started out infinitely large 13.8 billion >> years ago and still be expanding today, it could even be accelerating. The >> radius of the observable universe is 45.5 billion light years ( the light >> from the most distant galaxies took 13.8 billion years to reach us but >> during that time the galaxies have been accelerating away from us) but that >> doesn't mean there aren't galaxies much more distant than 45.5 billion >> light years. >> >> John K Clark >> > > If the universe was infinite in spatial extent at the time of, or > immediately after the BB, the various parts wouldn't have been causally > connected and we wouldn't need inflation to preserve (a non existent) > homogeneity. It's because it was small at the time of, or just after the > BB, that inflation was imagined to preserve the original homogeneity. FWIW, > I'm convinced our bubble is a finite hypersphere, almost but not flat, due > to its huge size. 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/3502b25c-99a0-414c-acf4-9b301c2bcdc0%40googlegroups.com.
