The four-point correlation function of graviton during inflation

  title={The four-point correlation function of graviton during inflation},
  author={Tianfu Fu and Qing Guo Huang},
  journal={Journal of High Energy Physics},
  • Tianfu FuQ. Huang
  • Published 9 February 2015
  • Physics, Geology
  • Journal of High Energy Physics
A bstractWe expand the Einstein-Hilbert action with a positive cosmological constant up to the fourth order in terms of gravity fluctuations, and then use the in-in formalism to calculate the four-point correlation function for gravitational waves, including both contact and exchange diagrams, generated during a period of exactly de Sitter expansion. In addition, we also present the general properties of the n-point function of graviton in terms of both circularly and linearly polarized states. 

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