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An infinite energy?

  1. Sep 11, 2013 #1
    In gravitational field its a constant exchange of photons right? Then in ideal circumstances, if one object orbits the other one forever, then it means we get the exchange of photons forever right?which means infinite energy, I get that it can't be observed but thats possible for infinite energy to exist right?
     
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  3. Sep 11, 2013 #2

    ZapperZ

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    This appears to be your starting premise, and it is imperative that you get this right (which it isn't) FIRST and foremost. So can you please cite a proper source to back this up?

    If not, the rest of what you have written is moot, because it is based on a faulty concept.

    Zz.
     
  4. Sep 11, 2013 #3
    I read a thread on this forum :D
     
  5. Sep 11, 2013 #4
    Best to post the link to that thread.
     
  6. Sep 11, 2013 #5

    Drakkith

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    Not only is gravity not mediated by photons, but theoretically by gravitons, these gravitons would be virtual gravitons and you would not be able to get infinite energy.
     
  7. Sep 11, 2013 #6
    But things like planets, stars, even galaxies, are not ideal and do not 'orbit forever'....the orbits slowly decay.

    A short bit here:
    http://en.wikipedia.org/wiki/Orbital_decay#By_gravitational_radiation

    edit: just remembered this discussion is in "quantum physics'.....
    so better to check here:
    http://en.wikipedia.org/wiki/Atomic_orbital

    For subatomic particles, no gravity has yet been included in the Standard Model of Particle physics
     
  8. Sep 11, 2013 #7

    ZapperZ

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    This is lazy and unacceptable. Cite the link to the exact thread!

    https://www.physicsforums.com/blog.php?b=2703 [Broken]

    Zz.
     
    Last edited by a moderator: May 6, 2017
  9. Sep 11, 2013 #8

    Drakkith

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    While true, even if they did not lose energy to gravitational waves, it would still not be infinite energy. I just want to make sure the OP understands that.
     
  10. Sep 12, 2013 #9
    I am really sorry for that, it was a long ago.I assume that it was about the electrical field and I somehow understood it that way

    Wait so what does "losing energy to gravitational waves" mean? By Newtonian mechanics it would have been easily explained, in ideal circumstances it would move evenly, which means no force,no energy.But it takes speed of light for gravitational field to travel right? So theres no quants of energy traveling?
     
    Last edited by a moderator: May 6, 2017
  11. Sep 12, 2013 #10

    Drakkith

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    In general relativity two orbiting bodies lose orbital energy by emitting waves in the metric, aka gravitational waves.

    In newtonian mechanics there is no such thing as a gravitational wave because there is no metric. Also, it is important to understand that a static field does not propagate. It is only changes in that field that propagate.

    Finally, don't confuse regular photons and other force carrier particles with their virtual counterparts. It is these virtual particles that mediate forces.
     
  12. Sep 12, 2013 #11

    ZapperZ

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    Then either your memory got corrupted, or you understood the wrong thing. This is why we require that you cite the source completely. After all, none of us here want to defend and explain something that is wrong.

    Gravity isn't mediated by photons. Photons (virtual ones) are responsible for all electromagnetic interactions as described using quantum field theory.

    So the starting premise of your thread is false.

    Zz.
     
  13. Sep 12, 2013 #12

    Akaisora

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    Use the search function and search for keywords to find the thread.
     
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