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Ripple deSitter universe-Randono cannonball analog

  1. Jun 18, 2008 #1

    marcus

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    Ripple deSitter universe---Randono cannonball analog

    Look at Figure 2 in this paper (scroll to page 9 of the PDF download)
    http://arxiv.org/abs/0805.2955
    the size of the universe ripples down to a state of maximum concentration and then re-expands, again in quasi-stepwise ripples.

    What does this have to do with the classic cannonball arc trajectory?
    As we know from Galileo and from the college physics textbook, if you shoot a particle up in free fall it will make a parabola trajectory, approximately. It will rise to some maximum and have a turning point and fall back to earth.
    Well a few years ago, in France, they did some experiments with NEUTRONS in free fall and found that the particle rises stepwise and then falls back stepwise.

    The neutron is just like a cannonball except with small enough mass that you can detect and measure the ripples. A particle in free fall does not follow a parabola. It follows a parabola with ripples superimposed on it. It rises and descends in quasi steps.

    In the case of neutron mass the scale of the steps is about 10 micron------or about 1/100 of a millimeter. Almost naked-eye visible hairline. Smaller masses would have larger steps. A neutrino trajectory would have steps on the order of one meter. It kind of fades from one level to the next.

    So what Randono found is that the size of the universe does the same thing.
     
  2. jcsd
  3. Jun 18, 2008 #2
    Surely you mean an ellipse.
     
    Last edited: Jun 18, 2008
  4. Jun 18, 2008 #3

    marcus

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    Of course I do :biggrin:, I said approximately.
    The familiar college textbook example of the ideal cannonball parabola arc....uniform gravitational field and all that.

    Just to put Randono's paper in context. He is part of Ashtekar's Penn State Loop Quantum Cosmology group.
    LQC is currently the lead approach in quantum cosmology (the research area which addresses stuff like resolving the the bigbang singularity)
    http://www.slac.stanford.edu/spires...+date+>+2005&FORMAT=WWW&SEQUENCE=citecount(d)

    with recent quantum cosmology papers ranked by citation count, Loop represents 9/10 of the top ten, and 17/20 of the top twenty.
    So without saying anything about how likely it is to be right or wrong, it is worth knowing about simply because it is the current mainstream leader. And Randono's work is part of that current development in cosmology.
     
    Last edited: Jun 18, 2008
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