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How do we know Inflation begin in 10^-35 second?

  1. Mar 21, 2015 #1
    I am a high school student and I was searching the inflation theory.When I searched I found that inflation starts a certain time (10-35) how physicists know that 10-35 is the "true" or"right" time ?
  2. jcsd
  3. Mar 21, 2015 #2


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    We don't even know for sure that inflation happened. It probably did and it certainly solves some otherwise difficult problems in cosmology, but its occurrence is not known for a fact. How the figure of 10^-35 was arrived at I don't know, and I have seen slightly different figures for both the start and the end of the period, although all agree that it was very brief.
  4. Mar 21, 2015 #3


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    This is basically a guess. Within inflation, it is unclear when inflation started or how long it lasts, as inflation wipes out almost all evidence of anything that came before.
  5. Mar 21, 2015 #4


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    In Linde's chaotic model, inflation begins at the Planck time [10^-43]. In other models it begins around the time of the electroweak epoch [10^-36]. In all models it is generally agreed to have ended when the universe was about 10^-32 seconds in age. Bear in mind we still lack any compelling evidence that inflation actually occured, so, it's still just a guess, as Chalnoth pointed out. You will notice all of these 'guess' times coincide with phase transitions in the early universe. At Planck time it is believed the gravitational force had just separated from the primordial super state, when all the known forces in the universe were combined. At the time of the electroweak epoch, the strong nuclear force had just separated from the state known as grand unification, when all the known forces save gravity were still combined.
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