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Nonlinear Lagrangians of the Ricci type

Andrzej Borowiec
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Abstract

The Euler-Lagrange equations for some class of gravitational actions are calculated by means of Palatini principle. Polynomial structures with Einstein metrics appear among extremals of this variational problem.

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Andrzej Borowiec. 1999-06-13. Nonlinear Lagrangians of the Ricci type. https://arxiv.org/abs/gr-qc/9906043

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