On Sunday, December 23, 2018 at 2:17:14 AM UTC, John Clark wrote: > > On Sat, Dec 22, 2018 at 6:46 AM <[email protected] <javascript:>> wrote: > > *> If the temperature was non uniform when the BB occurred, if it >> occurred, why would a sudden increase in its volume, aka inflation, erase >> or wash out those non uniformities?* >> > > Regardless of how non-uniform the entire early universe may have been if > you kept looking at smaller and smaller volumes you'd eventually find a > size where thing were pretty uniform. If inflation theory is correct that > small nearly uniform part of the universe started to expand exponentially; > that > is to say it had a fixed doubling time, every 10^-37 seconds the diameter > of that small part of the universe doubled, and in 10^-35 seconds it > doubled a hundred times and became our observable universe. It has continued > to expand to this day but at a much much more leisurely rate. > > >> > *OTOH, if the initial temperature were uniform, would that obviate the >> need for inflation, or would non uniformities tend to become manifest were >> it not for inflation?* >> > > Without inflation its very hard to understand how the temperature could be > uniform because there wasn't enough time for the temperature to equalize, > the distance parts of the universe were neven is causal comtact and yet > they are at the same temperature to one part in 100,000. >
*CMIIAW, but you're assuming the initial BB temperature was non uniform and inflation is needed to get the uniform temperature we observe. The problem with this is that (by applying your argument in first paragraph) one would expect an infinitesimally small universe to have a uniform temperature. Thus, inflation doesn't seem necessary to get to uniformity. It only serves to explain the flatness. BTW, how is the curvature of the universe measured? TIA, AG * > > 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 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.
