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Are gravitons the quanta of spacetime?

  1. Feb 16, 2016 #1
    In QFT, an ultraviolet cutoff is imposed to avoid singularities. One physical reason for why this works may be that there actually is an ultraviolet cutoff from spacetime being quantized. Since in GR spacetime is responsible for the force of gravity, and gravitons are the hypothesized quanta of gravity, would gravitons be quantized spacetime, or are they distinct?
  2. jcsd
  3. Feb 16, 2016 #2


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    Yes. (But the cutoff not prevent spacetime from being quantized - the graviton can exist as a low energy approximation even if there is a cutoff, eg. http://arxiv.org/abs/hep-th/0407039.)

    "In an attempt to explain the meaning of “empty space” to a young child, I said “space is something not made of atoms.” He replied “Then you were wrong to tell me last time that only light is not made of atoms.” Indeed, light and gravity are two singular forms of “matter” which are very different from other forms of matter such as atoms, electrons, etc . (Here I assume space = gravity.) The existences of light and gravity – two massless gauge bosons – are two big mysteries in nature.

    Massless particles are very rare in nature. In fact photon and graviton are the only two massless particles known to exist."

    From http://arxiv.org/abs/hep-th/0109120
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