On Tuesday, December 25, 2018 at 2:13:46 AM UTC, [email protected] wrote: > > > > On Tuesday, December 25, 2018 at 12:35:24 AM UTC, Jason wrote: >> >> >> >> On Mon, Dec 24, 2018 at 6:28 PM <[email protected]> wrote: >> >>> >>> >>> On Monday, December 24, 2018 at 9:47:52 PM UTC, Jason wrote: >>>> >>>> >>>> >>>> On Mon, Dec 24, 2018 at 4:04 PM <[email protected]> wrote: >>>> >>>>> >>>>> >>>>> On Monday, December 24, 2018 at 8:25:11 PM UTC, [email protected] >>>>> wrote: >>>>>> >>>>>> >>>>>> >>>>>> On Monday, December 24, 2018 at 6:40:03 AM UTC, Brent wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On 12/23/2018 8:22 PM, [email protected] wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Monday, December 24, 2018 at 3:50:33 AM UTC, Brent wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 12/23/2018 4:47 PM, [email protected] wrote: >>>>>>>> >>>>>>>> *If by "flat", you mean mathematically flat, like a plane extending >>>>>>>> infinitely in all directions, as opposed to asymptotically flat like a >>>>>>>> huge >>>>>>>> and expanding sphere, you have to reconcile an infinitesimally tiny >>>>>>>> universe at the time of the BB, and simultaneously an infinitely large >>>>>>>> universe extending infinitely in all directions. AG* >>>>>>>> >>>>>>>> >>>>>>>> All that's "infinitesimally tiny" is the visible universe. You >>>>>>>> must know that the Friedmann equation just defines the dynamics of a >>>>>>>> scale >>>>>>>> factor, not a size. >>>>>>>> >>>>>>> >>>>>>> *Are you claiming the visible universe at the BB was infinitesimally >>>>>>> tiny, but the non visible part was infinitely large (mathematically >>>>>>> flat), >>>>>>> or huge (asymptotically flat)? AG * >>>>>>> >>>>>>> >>>>>>> Right. Although we can't be sure whether it is actually flat or >>>>>>> just very big. >>>>>>> >>>>>>> Brent >>>>>>> >>>>>> >>>>>> *OK. Agreed. We seemed to disagree on this in the past, but maybe we >>>>>> miscommunicated. AG* >>>>>> >>>>> >>>>> Here's what Ned Wright wrote. >>>>> >>>>> Is the Universe really infinite or just really big? >>>>> >>>>> We have observations that say that the radius of curvature of the >>>>> Universe is bigger than 70 billion light years. But the observations >>>>> allow >>>>> for either a positive or negative curvature, and this range includes the >>>>> flat Universe with infinite radius of curvature. The negatively curved >>>>> space is also infinite in volume even though it is curved. So we know >>>>> empirically that the volume of the Universe is more than 20 times bigger >>>>> than volume of the observable Universe. Since we can only look at small >>>>> piece of an object that has a large radius of curvature, it looks flat. >>>>> The >>>>> simplest mathematical model for computing the observed properties of the >>>>> Universe is then flat Euclidean space. This model is infinite, but what >>>>> we >>>>> know about the Universe is that it is really big >>>>> <http://www.astro.ucla.edu/~wright/HGTTG.html>. >>>>> >>>>> >>>>> <http://www.astro.ucla.edu/~wright/cosmology_faq.html#top> >>>>> >>>>> *It is misleading. He's referring to the VISIBLE universe and >>>>> concludes it might be infinite in spatial extent. Impossible due to its >>>>> finite age. I wrote him about this, but never received a reply. AG* >>>>> >>>>> >>>>> >>>> It's only impossible if you believe the believe the big bang occurred >>>> only at a point, rather than everywhere. >>>> >>>> Consider that every point in space sees everything else around it >>>> flying away from it, such that if you rewound time, everything would >>>> return >>>> to a single point centered at that location. But this is true for every >>>> point in space, so the implication is that the BigBang didn't happen at >>>> one >>>> particular location long in the past, but at every point, including the >>>> period at the end of this sentence. >>>> >>> >>> *You seem inclined to extreme hypotheses for which there is no data. AG * >>> >>>> >>>> >> This is the default "standard" model used used by cosmologists, it's >> called the concordance model, or the Lambda-CDM model. There is significant >> data for it. >> > > *I don't believe it. AG * >
*I mean I don't believe your interpretation of the Concordance model. AG * > > >> Jason >> > -- 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.
