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Isotropic cosmologies in Weyl geometry

John Miritzis
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Abstract

We study homogeneous and isotropic cosmologies in a Weyl spacetime. We show that for homogeneous and isotropic spacetimes, the field equations can be reduced to the Einstein equations with a two-fluid source. We write the equations as a two-dimensional dynamical system and analyze the qualitative, asymptotic behavior of the models. We examine the possibility that in certain theories the Weyl 1-form may give rise to a late accelerated expansion of the Universe and conclude that such behaviour is not met as a generic feature of the simplest cosmologies.

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John Miritzis. 2004-02-09. Isotropic cosmologies in Weyl geometry. https://doi.org/10.1088/0264-9381%2F21%2F12%2F014

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