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arXiv · 1003.4701

Bi-metric theory of gravity from the non-chiral Plebanski action

Simone Speziale
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Abstract

We study a modification of the Plebanski action for general relativity, which leads to a modified theory of gravity with eight degrees of freedom. We show how the action can be recasted as a bi-metric theory of gravity, and expanding around a bi-flat background we identify the six extra degrees of freedom with a second, massive graviton and a scalar mode.

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Simone Speziale. 2010-08-14. Bi-metric theory of gravity from the non-chiral Plebanski action. https://doi.org/10.1103/physrevd.82.064003

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