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arXiv · 0812.3200

Modified gravity without new degrees of freedom

Laurent Freidel
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Abstract

We show that the new type of "non-metric" gravity theories introduced independently by Bengtsson and Krasnov can in fact be reexpressed explicitely as a metrical theory coupled to an auxiliary field. We unravel why such theories possess only one propagating graviton by looking at the quadratic perturbation around a fixed solution. And we give a general construction principle with a new class of example of such modified gravity theories still possessing only two propagating degrees of freedom.

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Laurent Freidel. 2008-12-17. Modified gravity without new degrees of freedom. https://arxiv.org/abs/0812.3200

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