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How can gravitons be linked to general relativity?

  1. Apr 17, 2014 #1
    Hi, this might be a silly question, but it does confuse me when I read about general relativity. From what I know about quantum mechanics, a force always needs a force carrier. For example photons are force-carriers for electric or magnetic force; the so-called ‘gravitons’ are the force-carriers for gravitational force. However, general relativity states that gravity is not a force; it’s just the effects of the bending of space-time near a massive object. So why do we need the graviton at all? In other words, how can the graviton be linked to the bending of space-time?

    Thank you :)
  2. jcsd
  3. Apr 17, 2014 #2


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    Science Advisor
    Gold Member

    When you take GR in the weak gravitational limit (e.g., like Newtonian gravity), and quantize it ... you find these spin 2 bosons. These are what they call gravitons.

    Whether or not they actually exist is another question.

    But it is not quantum gravity, and it is not general relativity.
  4. Apr 17, 2014 #3


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    Staff: Mentor

    Tip: if you look down at the bottom of this page, you will find a list of "Related Discussions" with the very same (or nearly same) question that you asked. This is a rather frequently asked question here.
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