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Formation of cosmological mass condensation within a FRW universe: exact general relativistic solutions

Samad Khakshournia·Reza Mansouri
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Abstract

Within the framework of an exact general relativistic formulation of gluing manifolds, we consider the problem of matching an inhomogeneous overdense region to a Friedmann-Robertson-Walker background universe in the general spherical symmetric case of pressure-free models. It is shown that, in general, the matching is only possible through a thin shell, a fact ignored in the literature. In addition to this, in subhorizon cases where the matching is possible, an intermediate underdense region will necessarily arise.

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Samad Khakshournia, Reza Mansouri. 2003-07-06. Formation of cosmological mass condensation within a FRW universe: exact general relativistic solutions. https://doi.org/10.1103/physrevd.65.027302

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