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Lanczos potentials and a definition of gravitational entropy for perturbed FLRW space-times

Filipe C. Mena·Paul Tod
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Abstract

We give a prescription for constructing a Lanczos potential for a cosmological model which is a purely gravitational perturbation of a Friedman-Lemaitre-Robertson-Walker space-time. For the radiation equation of state, we find the Lanczos potential explicitly via Fourier transforms. As an application, we follow up a suggestion of Penrose and propose a definition of gravitational entropy for these cosmologies. With this definition, the gravitational entropy initially is finite if and only if the initial Weyl tensor is finite.

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Filipe C. Mena, Paul Tod. 2007-02-09. Lanczos potentials and a definition of gravitational entropy for perturbed FLRW space-times. https://doi.org/10.1088/0264-9381%2F24%2F7%2F004

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