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Cosmological horizon still is at the big bang

  1. Nov 10, 2011 #1
    "There are two ways to describe a spacetime with a horizon: global and local. The global picture includes regions beyond the horizon, which are invisible to us, while the local picture is the picture from one point of view only. These two perspectives are related by a process of extension, wherever there is a horizon, a solution of General Relativity can go on by assuming that nothing special happens there. The local and global points of view have a different notion of time. From the local point of view, time stops at the horizon. From the global point of view, time marches on, and surfaces of constant time cross the horizon. Ignoring quantum mechanics, the two pictures are equivalent: any statement can be translated freely back and forth.
    In the local point of view, the cosmological horizon still is at the big bang, and inflation is always going on in a thin skin where time is nearly stopped, and the same process produces new regions as it always did, up to small fluctuations."

    I'm confused by the statement in bold. Can anyone expound upon this explanation?
  2. jcsd
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