Non-Gaussianity of quantum fields during inflation

  title={Non-Gaussianity of quantum fields during inflation},
  author={Kazuya Koyama},
  journal={Classical and Quantum Gravity},
  • K. Koyama
  • Published 3 February 2010
  • Physics
  • Classical and Quantum Gravity
In this paper, we discuss how non-Gaussianity of cosmological perturbations arises from inflation. After introducing the in–in formalism to calculate the n-point correlation function of quantum fields, we present the computation of the bispectrum of the curvature perturbation generated in general single-field inflation models. The shapes of the bispectrum are compared with the local-type non-Gaussianity that arises from nonlinear dynamics on super-horizon scales. 

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