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arXiv · 1903.11638

Scalar charges and pulsar-timing observables in the presence of nonminimally coupled scalar fields

Raissa F. P. Mendes·Tulio Ottoni
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Abstract

Pulsar-timing has become a celebrated tool for probing modifications to General Relativity in the strong-field surroundings of neutron stars. Here we investigate whether scalar-tensor theories that incorporate a nonminimally coupled scalar degree of freedom may pass pulsar-timing tests, by computing the scalar charges entering such observables. In particular we show that for positive values of the nonminimal coupling $\xi$, pulsar-timing constraints may be evaded even in the presence of spontaneous scalarization.

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Raissa F. P. Mendes, Tulio Ottoni. 2019-03-27. Scalar charges and pulsar-timing observables in the presence of nonminimally coupled scalar fields. https://doi.org/10.1103/physrevd.99.124003

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