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Local spherically symmetric perturbations of spatially flat Friedmann models

A. A. Popov·R. K. Muharlyamov
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Abstract

The spherically symmetric perturbations in the spatially flat Friedman models are considered. It is assumed that the Friedmannian density and pressure are related through a linear equation of state. The perturbation is joined smoothly with an unperturbed Friedmann's background at the sound horizon of perturbation. Such junction is in accordance with the "birth" of a local perturbation as a result of the redistribution of matter. The solution of the Einstein's equations is obtained in linear approximation on a Friedmann's background near the the sound horizon of perturbation.

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A. A. Popov, R. K. Muharlyamov. 2006-10-27. Local spherically symmetric perturbations of spatially flat Friedmann models. https://arxiv.org/abs/gr-qc/0610137

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