A new paper has a handy chart assigning red shift time frames for key eras derived from from standard cosmology assumptions to specific numbers of years after the Big Bang, and the ambient temperature at each point. See also a related Wikipedia page on the chronology of the universe.
The chart starts at what might fairly be called the midpoint of the "Photon epoch" and after Big Bang nucleosynthesis (which takes place from roughly 10 seconds to 1000 seconds after the Big Bang).
The energy scales which have been probed by the Large Hadron Collider (LHC) reach the energy scales associated in the standard cosmology chronology with 10^-12 seconds (i.e. one trillionth of a second) after the Big Bang. In this account:
The sphere of space that will become the observable universe is approximately 300 light-seconds (~0.6 AU) in radius at this time.
So, the time frame in which beyond the Standard Model physics that only manifest at extremely high energies (assuming that the Standard Model is merely a "low energy" effective field theory) is physically relevant is very, very short.
The epochs that precede this point, the "Electroweak epoch", the "Inflationary epoch", the "Grand Unification epoch", and the "Planck epoch" are all high speculative (especially the "Inflationary epoch", the "Grand Unification epoch", and the "Planck epoch."). In the highly speculative inflationary epoch account:
Cosmic inflation expands space by a factor of the order of 10^26 over a time of the order of 10^−36 to 10^−32 seconds.
The paradigm of Grand Unification has increasingly fallen into disfavor.
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