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I Time in physics and cosmology

  1. Jul 4, 2016 #1
    The Pi just posted a bunch of videos from their conference on time
    http://pirsa.org
    A lot of the big names in cosmology were there: Sean Carroll, Lee Smolin, Abhay Ashtekar , Andy Albrecht, George Ellis etc
    I have to say though I'm a little surprised at some of the questions. How is it i ( layman in this field ) knows that LQC isn't a cyclic model but Andy Albrecht one of the world experts ,doesn't? It makes me think there is far too much compartmentalisation in science, but maybe thats inevitable . Anyway this conference seemed to bring people together form different research programmes and is very interesting if you have the time.
     
  2. jcsd
  3. Jul 4, 2016 #2

    Chalnoth

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    Why do you think LQC isn't a cyclic model?
     
  4. Jul 4, 2016 #3
    As I understand it , it gives corrections to the Gr at high curvature, replacing the big bang singularity with a bounce. it doesn't make predictions about dark energy turning around and causing a recollapse and hence it is not a cyclic model.
     
  5. Jul 5, 2016 #4

    Chalnoth

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    https://arxiv.org/abs/1507.00226
    https://arxiv.org/abs/hep-th/0407115

    I believe a universe with a bounce is frequently called "cyclic" even if there isn't an infinite chain of cycles.
     
  6. Jul 5, 2016 #5
    I have no idea how it can possibly be appropriate to call a universe that contracts and then expands but never repeats this process a cyclic one. One that repeats the process sure, but one that doesn't? i don't see how that makes sense.
     
  7. Jul 5, 2016 #6
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