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Red shift, gravity, and dark energy.

  1. Jul 17, 2010 #1
    When matter is transformed into light energy within a star, the gravity associated with the matter is now associated with the light's energy. As space expands, the redshift is dilluting the light's energy and reducing the gravity associated with that energy. Would the energy dillution further weaken the gravitational bonds between galaxies in addition to the expansion itself, giving the appearence of dark energy acceleration?
  2. jcsd
  3. Jul 17, 2010 #2


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    No. Dark Energy acceleration is not weaker gravity, it's antigravity. Have a look at https://www.physicsforums.com/showthread.php?t=415607".
    Last edited by a moderator: Apr 25, 2017
  4. Jul 18, 2010 #3


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    Nope, doesn't work this way. The energy emitted as light from a star stems directly from the nuclear reaction at its core. Except for brown dwarfs, stars are stable objects which do not collapse under gravity for the majority of their life cycle. The gravity of a star is entirely separate.

  5. Jul 18, 2010 #4
    This is a result of frame-dependence in the measurement which leads to the appearance of energy attenuation, right?
  6. Jul 19, 2010 #5
    Last edited by a moderator: Apr 25, 2017
  7. Jul 19, 2010 #6
    Chal, I am going to post another topic on this to better understand.
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