- #1
Naty1
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I am wondering whether discussions of inflationary cosmology in these forums generally includes or explicitly excludes prior Plank era and GUT era dynamics. I never gave it any thought until reading the following.
The Wikipedia article provides a perspective I just don't remember from other sources. If inflationary cosmology excludes Planck and GUT eras, are there some alternative pre inflationary dynamics we are supposed to associate with inflation?
http://en.wikipedia.org/wiki/Chronology_of_the_universe
[my boldface emphasis]
[again my bold]
Why is the age of the universe less certain when we stick in inflation??
The Wikipedia article provides a perspective I just don't remember from other sources. If inflationary cosmology excludes Planck and GUT eras, are there some alternative pre inflationary dynamics we are supposed to associate with inflation?
http://en.wikipedia.org/wiki/Chronology_of_the_universe
[my boldface emphasis]
...In modern inflationary cosmology, the traditional grand unification epoch, like the Planck epoch, does not exist, though similar conditions likely would have existed in the universe prior to inflation...
okThe Planck epoch is an era in traditional (non-inflationary) big bang cosmology...
[again my bold]
...In inflationary cosmology, times before the end of inflation (roughly 10−32 second after the Big Bang) follow not the traditional big bang timeline. The universe before the end of inflation is a very cold near-vacuum and persists for much longer than 10−32 second. Times from the end of inflation are based on the big bang time of the non-inflationary big bang model, not on the actual age of the universe at that time, which cannot be determined in inflationary cosmology. Therefore, inflationary cosmology lacks a traditional Planck epoch--though similar conditions may have prevailed in a pre-inflationary era of the universe.
Why is the age of the universe less certain when we stick in inflation??