On Thursday, January 23, 2020 at 3:54:31 AM UTC-7, John Clark wrote: > > On Wed, Jan 22, 2020 at 9:53 PM Alan Grayson <[email protected] > <javascript:>> wrote: > > >>If empty space has a residual intrinsic energy of any value greater >>> than zero, which General Relativity allows for and Quantum Mechanics >>> demands, >>> >> >> > *WRT QM, are you depending on the HUP to make this statement? AG* >> > > Quantum Mechanics demands that virtual particles give empty space an > intrinsic energy, although the number it came up with was 10^120 times > larger than what the observed value turned out to be. >
That's what QED gives for the summed vacuum state energy of every frequency mode, assuming some cutoff. Since it's clearly wrong, no point in using it in an argument. And nothing to do with virtual particles, at least as far as QED is concerned. AG And IHA. > > >> then the expansion of the universe will accelerate. >>> >> >> *> Why? * >> > > Because that's what the 4D tensor equations of General Relativity say. > > >> >> If the universe is accelerating then it is open regardless of what >>> its spatial shape is, regardless of how many degrees the angles of a >>> triangle add up to (please remember the term "spatial shape" is not >>> equivalent with the term "spacetime shape"). >>> >> >> *> Maybe the issue is whether the universe has infinite or finite volume, >> and "closure" is irrelevant? AG * >> > > When you ask "is the universe infinite?" if you don't mean can you keep > getting further from your starting point forever then I don't know what you > mean by the question. > I mean the total volume is finite at any moment in time, even though its volume is increasing without limit, while the matter content remains constant. AG > > *> **A hyper-sphere has no edge or boundary, and if it is expanding, you >> might never return to your starting point* >> > > Exactly. > > *> even though it is finite in spatial volume.* >> > > If the Universe is finite then you should be able to visit every cubic > meter of it, at least in principle. > There's no such principle, and in fact it's wrong. Just imagine an expanding hyper-sphere, even one expanding at less than light speed, and you'll see your conjecture isn't true. AG > But in a expanding and accelerating universe you can't. > > 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/4a56dbc1-7573-47f7-8b2b-bc8f024158f2%40googlegroups.com.
