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arXiv · 1008.2246

Beyond Spherical Top Hat Collapse

T. S. Pereira·R. Rosenfeld·A. Sanoja
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Abstract

We study the evolution of inhomogeneous spherical perturbations in the universe in a way that generalizes the spherical top hat collapse in a straightforward manner. For that purpose we derive a dynamical equation for the evolution of the density contrast in the context of a Lemaitre-Tolman-Bondi metric and construct solutions with and without a cosmological constant for the evolution of a spherical perturbation with a given initial radial profile.

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T. S. Pereira, R. Rosenfeld, A. Sanoja. 2010-08-13. Beyond Spherical Top Hat Collapse. https://doi.org/10.1209/0295-5075%2F92%2F39001

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