2009

Non-Gaussianity Generated by the Entropic Mechanism in Bouncing Cosmologies Made Simple

Lehners, Jean-Luc, Steinhardt, Paul J.

Understand

Non-gaussianity in the microwave background radiation is bound to play a key role in giving us clues about the physics of the very early universe.

  • However, the associated calculations, at second and even third order in perturbation theory, tend to be complicated to the point of obscuring simple underlying physical processes.
  • In this note, we present a simple analytic procedure for approximating the non-linearity parameters f_{NL} and g_{NL} for cyclic models in which the cosmological perturbations are generated via the entropic mechanism.
  • Our approach is quick, physically transparent and agrees well with the results of numerical calculations.

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