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Why does Einsteinian gravity need waves or gravitons?

  1. Feb 21, 2016 #1
    Hi Everyone, my first post here.

    I'm really confused by the comments around the recent LIGO gravitational waves discovery and how it connects to Einsteins gravitational model. My understanding is that he said a body warped spacetime around it forming a gravitational well into which other bodies would 'fall into'. This relies entirely on the topography of spacetime with no force carrying particles or waves needed for this model.

    Can anyone explain please?

  2. jcsd
  3. Feb 21, 2016 #2


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    Staff: Mentor

    Gravitons are hypothetical particles that appear in some unconfirmed quantum mechanical theories of gravity. They are no part of general relativity (Einstein's theory of gravity) so they are neither required nor precluded by it.

    Gravitational waves aren't required by general relativity either - it's the other way around. You write down the equations of general relativity (the Einstein Field Equations), you solve them, and under certain conditions one of the solutions is gravitational waves.
  4. Feb 22, 2016 #3
    Thanks Nugatory. Having no higher maths at all I won't be solving any of those equations soon. Could you point me to anywhere where I could read an abstract of the conditions and/or solutions you mention?

    Thanks. :smile:
  5. Feb 22, 2016 #4


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    Staff Emeritus
    Science Advisor

  6. Feb 22, 2016 #5
    Thanks very much Drakkith.
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