TY - JOUR
T1 - Non-Gaussianity generated by the entropic mechanism in bouncing cosmologies made simple
AU - Lehners, Jean Luc
AU - Steinhardt, Paul J.
N1 - Copyright:
Copyright 2009 Elsevier B.V., All rights reserved.
PY - 2009/11/24
Y1 - 2009/11/24
N2 - Nongaussianity 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 nonlinearity parameters fNL and gNL 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.
AB - Nongaussianity 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 nonlinearity parameters fNL and gNL 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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U2 - 10.1103/PhysRevD.80.103520
DO - 10.1103/PhysRevD.80.103520
M3 - Article
AN - SCOPUS:72049130275
VL - 80
JO - Physical Review D - Particles, Fields, Gravitation and Cosmology
JF - Physical Review D - Particles, Fields, Gravitation and Cosmology
SN - 1550-7998
IS - 10
M1 - 103520
ER -