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arXiv · astro-ph/0108283

Nonlinear evolution of spherical perturbation in a non-flat Universe with cosmological constant

Ewa L. Lokas·Yehuda Hoffman
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Abstract

We generalize the spherical collapse model for the formation of bound objects to apply in a Universe with arbitrary positive cosmological constant. We calculate the critical condition for collapse of an overdense region and give exact values of the characteristic densities and redshifts of its evolution.

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Ewa L. Lokas, Yehuda Hoffman. 2002-07-25. Nonlinear evolution of spherical perturbation in a non-flat Universe with cosmological constant. https://arxiv.org/abs/astro-ph/0108283

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