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Structure formation in the Lemaitre-Tolman model

Andrzej Krasinski·Charles Hellaby
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Abstract

Structure formation within the Lemaitre-Tolman model is investigated in a general manner. We seek models such that the initial density perturbation within a homogeneous background has a smaller mass than the structure into which it will develop, and the perturbation then accretes more mass during evolution. This is a generalisation of the approach taken by Bonnor in 1956. It is proved that any two spherically symmetric density profiles specified on any two constant time slices can be joined by a Lemaitre-Tolman evolution, and exact implicit formulae for the arbitrary functions that determine the resulting L-T model are obtained. Examples of the process are investigated numerically.

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Andrzej Krasinski, Charles Hellaby. 2001-10-31. Structure formation in the Lemaitre-Tolman model. https://doi.org/10.1103/physrevd.65.023501

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