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arXiv · 0709.3863

Exact and Perturbed Friedmann-Lemaitre Cosmologies

Paul Ullrich
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Abstract

In this thesis we first apply the 1+3 covariant description of general relativity to analyze n-fluid Friedmann-Lemaitre (FL) cosmologies; that is, homogeneous and isotropic cosmologies whose matter-energy content consists of n non-interacting fluids. We are motivated to study FL models of this type as observations suggest the physical universe is closely described by a FL model with a matter content consisting of radiation, dust and a cosmological constant. Secondly, we use the 1+3 covariant description to analyse scalar, vector and tensor perturbations of FL cosmologies containing a perfect fluid and a cosmological constant. In particular, we provide a thorough discussion of the behaviour of perturbations in the physically interesting cases of a dust or radiation background.

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Paul Ullrich. 2007-09-25. Exact and Perturbed Friedmann-Lemaitre Cosmologies. https://arxiv.org/abs/0709.3863

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