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arXiv · 2012.05850

The radiation instability in modified gravity

Spiros Cotsakis·Dimitrios Trachilis
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Abstract

We study the problem of the instability of inhomogeneous radiation universes in quadratic lagrangian theories of gravity written as a system of evolution equations with constraints. We construct formal series expansions and show that the resulting solutions have a smaller number of arbitrary functions than that required in a general solution. These results continue to hold for more general polynomial extensions of general relativity.

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Spiros Cotsakis, Dimitrios Trachilis. 2021-03-23. The radiation instability in modified gravity. https://doi.org/10.1142/s0217751x21500603

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