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arXiv · 2605.20611

Gravitational entropy in Petrov Type I spacetimes

Maharshi Sarma·Sebastián Nájera·Roberto A. Sussman
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Abstract

The gravitational entropy proposal of Clifton, Ellis and Tavakol (CET) is based on an effective energy momentum tensor formed by the algebraic decomposition of the 4th order Bel-Robinson tensor. So far the application of the CET proposal has been limited to spacetimes of Petrov types D and N for which this algebraic decomposition is unique. To address this limitation we examine in detail the effective energy momentum tensors that result from the algebraic decomposition of the Bel-Robinson tensor in Petrov type I spacetimes. As a test case we apply these results to the Szekeres models of class II, a Petrov type I analytic solution.

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Maharshi Sarma, Sebastián Nájera, Roberto A. Sussman. 2026-05-20. Gravitational entropy in Petrov Type I spacetimes. https://arxiv.org/abs/2605.20611

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