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Two loop corrections

  1. Dec 16, 2007 #1
    I have been reading a Weinberg paper (the cosmological constant problem), where he writes

    "...Zeldovich assumed that these were cancelled leaving only the higher order effects: in particulal, the gravitational force between the particles in the vacuum fluctuations. (In Feynman diagram terms, this corresponds to throwing away te one-loop graphs, but keeping those with two loops"

    Can someone help me understand this. I thought QFT said nothing about gravity. Why do the two loops correspond to the gravitational force??
  2. jcsd
  3. Dec 18, 2007 #2

  4. Dec 18, 2007 #3


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    You might have better luck if you cite the paper.
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