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arXiv · 0805.1834

Maximal symmetry and metric-affine f(R) gravity

Tuomas Multamäki·Jaakko Vainio·Iiro Vilja
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Abstract

The affine connection in a space-time with a maximally symmetric spatial subspace is derived using the properties of maximally symmetric tensors. The number of degrees of freedom in metric-affine gravity is thereby considerably reduced while the theory allows spatio-temporal torsion and remains non-metric. The Ricci tensor and scalar are calculated in terms of the connection and the field equations derived for the Einstein-Hilbert as wells as for f(R) Lagrangians. By considering specific forms of f(R), we demonstrate that the resulting Friedmann equations in Palatini formalism without torsion and metric-affine formalism with maximal symmetry are in general different in the presence of matter.

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Tuomas Multamäki, Jaakko Vainio, Iiro Vilja. 2008-05-13. Maximal symmetry and metric-affine f(R) gravity. https://doi.org/10.1088/0264-9381%2F26%2F7%2F075005

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