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arXiv · 2107.01187

Long-wavelength non-linear perturbations of a complex scalar field

Luis E. Padilla·Juan Carlos Hidalgo·Darío Núñez
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Abstract

We study the evolution of nonlinear superhorizon perturbations in a universe dominated by a complex scalar field. The analysis is performed adopting the gradient expansion approach, in the constant mean curvature slicing. We derive general solutions valid to second order in the ratio $H^{-1}/L$ for scalar field inhomogeneities of size $L$ subject to an arbitrary canonical potential. We work out explicit solutions for the quadratic and the quartic potentials, and discuss their relevance in setting initial conditions required for the simulations of Primordial Black Hole formation.

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Luis E. Padilla, Juan Carlos Hidalgo, Darío Núñez. 2021-07-02. Long-wavelength non-linear perturbations of a complex scalar field. https://doi.org/10.1103/physrevd.104.083513

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