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arXiv · 1906.01899

Gauge invariant formulation of gravitational waves in metric $f(R)$ gravity

Fabio Moretti·Flavio Bombacigno·Giovanni Montani
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Abstract

We analyze the gravitational waves propagation in metric $f(R)$ theories of gravity. In particular, adopting a gauge invariant formalism we clearly determine the exact propagating degrees of freedom. Then, investigating their effects on test masses via geodesic deviation equation, we show that the additional dynamical degree contained in such extended formulations is actually responsible for two distinguished polarizations, corresponding to a breathing and a longitudinal mode, respectively.

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Fabio Moretti, Flavio Bombacigno, Giovanni Montani. 2019-06-05. Gauge invariant formulation of gravitational waves in metric $f(R)$ gravity. https://doi.org/10.1103/physrevd.100.084014

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