On Monday, January 27, 2020 at 3:14:13 PM UTC-7, John Clark wrote: > > On Mon, Jan 27, 2020 at 2:18 PM Alan Grayson <[email protected] > <javascript:>> wrote: > > >>You can fit an infinite volume inside a expanding sphere if you take length >>> contraction into account.Einstein tells us that if the universe is a >>> expanding sphere then the more distant a star is from us the faster it >>> will be moving away from us and thus the thinner it will look to us, >>> this is even more important if it's not just expanding but accelerating. >> >> >> *> Failing to apply length contraction (and I'm not sure it is applicable >> in this situation),* > > > Interesting. Why aren't you sure? We know for a fact time runs slower > relative to us for an observer in a distant galaxy because we can see the > redshift, the decrease in frequency, of light that comes from there. But if > clocks ran slower for them but lengths did not also contract for them then > they would observe a different speed of light then we do. But we also know > for a fact from other experiments that the speed of light is the one true > constant for everyone everywhere, the observed speed of light does not > depend on the speed of the observer or on the speed of the source producing > the light. So why are you "not sure it is applicable in this situation"? >
*Simple. Because length contraction, say of a rod, depends on comparing measurement of the rod's length as observed in two frames of reference, moving wrt each other. In this case, we're making a measurement of the CMBR to determine curvature. AG* > > > *would just mean that the estimate without it would be too large, but >> not infinite. AG * > > > Neither Einstein's theory or anything else in physics says length > contraction, time dilation, and mass increase discontinuously stops at some > point short of the speed of light, they don't suddenly stop increasing, > they increase continuously up to the speed of light. > *I haven't stated anything about discontinuities. They don't exist in this situation. AG* > An expanding spherical universe that has a constant speed of causality > would follow 3D hyperbolic geometry just as MC Escher's woodcut "Circle > Limit III" follows 2D hyperbolic geometry. > > 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 view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/42b9e809-9f3c-49e6-acbf-303243fa663a%40googlegroups.com.
