• DOI:10.1103/PhysRevLett.127.101302
• Corpus ID: 228372632

Non-Gaussian Tail of the Curvature Perturbation in Stochastic Ultraslow-Roll Inflation: Implications for Primordial Black Hole Production.

@article{Figueroa2020NonGaussianTO,
  title={Non-Gaussian Tail of the Curvature Perturbation in Stochastic Ultraslow-Roll Inflation: Implications for Primordial Black Hole Production.},
  author={Daniel G. Figueroa and Sami Raatikainen and Syksy R{\"a}s{\"a}nen and Eemeli Tomberg},
  journal={Physical review letters},
  year={2020},
  volume={127 10},
  pages={
          101302
        }
}

• D. Figueroa, Sami Raatikainen, +1 author Eemeli Tomberg
• Published 11 December 2020
• Physics
• Physical review letters

We consider quantum diffusion in ultraslow-roll (USR) inflation. Using the ΔN formalism, we present the first stochastic calculation of the probability distribution P(R) of the curvature perturbation during USR. We capture the nonlinearity of the system, solving the coupled evolution of the coarse-grained background with random kicks from the short wavelength modes, simultaneously with the mode evolution around the stochastic background. This leads to a non-Markovian process from which we determine the highly non-Gaussian tail of P(R). Studying the production of primordial black holes in a viable model, we find that stochastic effects during USR increase their abundance by a factor of ∼10^{5} compared with the Gaussian approximation.