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arXiv · 0903.3407

Non-Gaussian Spikes from Chaotic Billiards in Inflation Preheating

J. Richard Bond·Andrei V. Frolov·Zhiqi Huang·Lev Kofman
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Abstract

A new class of non-Gaussian curvature fluctuations ζ_{pr} (\bx) \equiv δN(χ_i) arises from the post-inflation preheating behaviour of a non-inflaton field χ_i. Its billiard-like chaotic dynamics imprints regular log-spaced narrow spikes in the number of preheating e-folds N(χ_i). We perform highly accurate lattice simulations of SUSY-inspired quartic inflaton and coupling potentials in a separate-universe approximation to compute N(χ_i) as a function of the (nearly homogeneous) initial condition χ_i. The super-horizon modes of χ_i(\bx) result in positive spiky excursions in ζ_{pr} and hence negative gravitational potential fluctuations added to the usual sign-independent inflaton-induced perturbations, observably manifested in large cosmic structures and as (polarized) temperature CMB cold spots.

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J. Richard Bond, Andrei V. Frolov, Zhiqi Huang, Lev Kofman. 2009-03-20. Non-Gaussian Spikes from Chaotic Billiards in Inflation Preheating. https://doi.org/10.1103/physrevlett.103.071301

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