On Friday, October 4, 2019 at 7:32:32 AM UTC-5, Alan Grayson wrote: > > > > On Friday, October 4, 2019 at 4:50:12 AM UTC-6, Lawrence Crowell wrote: >> >> >> >> On Friday, October 4, 2019 at 5:34:42 AM UTC-5, Alan Grayson wrote: >>> >>> >>> >>> On Friday, October 4, 2019 at 3:31:31 AM UTC-6, Lawrence Crowell wrote: >>>> >>>> On Thursday, October 3, 2019 at 8:13:22 PM UTC-5, Alan Grayson wrote: >>>>> >>>>> On Thursday, October 3, 2019 at 7:05:12 PM UTC-6, Lawrence Crowell >>>>> wrote: >>>>>> >>>>>> On Thursday, October 3, 2019 at 8:01:49 PM UTC-5, Lawrence Crowell >>>>>> wrote: >>>>>>> >>>>>>> On Thursday, October 3, 2019 at 6:59:35 PM UTC-5, Bruce wrote: >>>>>>>> >>>>>>>> On Fri, Oct 4, 2019 at 9:54 AM Alan Grayson <agrays...@gmail.com> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> ISTM, that the argument the universe was NOT in thermo equilibrium >>>>>>>>> just before inflation is alleged to have begun, is extremely WEAK. >>>>>>>>> Thus, >>>>>>>>> it's illogical to claim that inflation "smooths out" the alleged NON >>>>>>>>> thermo >>>>>>>>> equiiibrium just before inflation begun. AG >>>>>>>>> >>>>>>>> >>>>>>>> That is essentially what I said. Lawrence is just replacing one set >>>>>>>> of unknown initial conditions with another, equally unjustified, set. >>>>>>>> >>>>>>>> Bruce >>>>>>>> >>>>>>> >>>>>> In below & means δ. I forgot to replace them. >>>>>> >>>>>> LC >>>>>> >>>>>> >>>>>>> >>>>>>> The entropy is S = A/4ℓ_p^2 + quantum corrections, where these >>>>>>> corrections are ~ (&S/&h^a)k^a. Here h^a is tangent to the horizon and >>>>>>> k^a >>>>>>> is normal. This condition coincident on a null surface can appear on a >>>>>>> quantum extremal surface with null tangent g^s so that (&S/&h^a)k^a ≥ >>>>>>> (&S/&g^a)k^a by subadditivity. However, this surface occurs inside the >>>>>>> cosmological horizon. This means there is no equilibriium. Equilibrium >>>>>>> is >>>>>>> only approximated by stretching the horizon out to enormous distance >>>>>>> after >>>>>>> the spatial surface has inflated. >>>>>>> >>>>>>> It is the case that inflation does not tell us the whole story prior >>>>>>> to inflation. So one can say there are equally unknown initial >>>>>>> conditions. >>>>>>> However, the details of those are less important as the spatial >>>>>>> manifold is >>>>>>> stretched out. That means inflation does provide at least a working >>>>>>> system. >>>>>>> >>>>>>> LC >>>>>>> >>>>>> >>>>> Assuming the universe was incredibly tiny prior to inflation, and was >>>>> therefore causally connected, isn't it reasonable to assume that it had >>>>> reached thermo equilibrium *prior* to the onset of inflation? AG >>>>> >>>> >>>> Thermal equilibrium is not possible with quantum fields in curved >>>> spacetiome, nor is is likely in quantum gravity. The reason is not too >>>> hard >>>> to see. Suppose you have a black hole in a thermal background with the >>>> same >>>> temperature as its horizon T ~ 1/8M. The black hole has an equiprobability >>>> of absorbing or emitting a photon with energy δM The temperature then >>>> adjusts as T - δT ~ 1/8(M + δM) or T + δT ~ 1/8(M - δM) and is shifted >>>> away >>>> from thermal equality. This will then enhance the probability the black >>>> hole either then grows by absorbing more photons or by emitting them. >>>> There >>>> is no thermal equilibrium. Quantum gravitation is likely the same, for the >>>> effective specific heat of event horizons is negative. What I wrote above >>>> is in effect a more general form of this. >>>> >>>> Now a gemish of particles or a gas can be in thermal equilibrium in >>>> spacetime. >>>> >>> >>> *Doesn't this characterize the universe before inflation began? If not, >>> then what? AG* >>> >> >> No, the large plasma of particles was generated in the post inflationary >> period with reheating or the collapse of the vacuum or inflaton. >> >> LC >> > > If not a plasma of particles before inflation, then what was it -- a soup > of photons, or what? Also, although I really don't know much about BH's, > your analysis above depends on a boundary between the BH and what's beyond > it. In the pre-inflation universe there was no internal boundary within the > universe, so I don't see the relevance of the BH analogy. AG >
I will write it one more time. Particles and radiation emerged in the observable universe, or this pocket world, with the collapse of the vacuum energy or inflaton by the mass-gap. The drop in vacuum energy produced the matter and radiation around us. LC > >> >>> >>> >>>> That was what was set up with inflation. The whole process of the early >>>> expanding universe is about there being episodes of approximate thermal >>>> equilibrium of particles, such as during the quark-gluon plasma phase, >>>> electroweak period, the QED equilibrium of electrons and photon or the >>>> plasma phase that ended by producing the CMB. >>>> >>>> To think about physics one has to do a sort of Buddhist middle way. It >>>> is not good to either be too liberal or given to extreme speculations, but >>>> it is also not good to be overly conservative. >>>> >>>> LC >>>> >>> -- 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 on the web visit https://groups.google.com/d/msgid/everything-list/6ff6f6fc-ddfe-4e74-abed-f30a90c6124c%40googlegroups.com.
