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arXiv · 1711.02080

Spontaneous scalarization of black holes and compact stars from a Gauss-Bonnet coupling

Hector O. Silva·Jeremy Sakstein·Leonardo Gualtieri·Thomas P. Sotiriou·Emanuele Berti
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Abstract

We identify a class of scalar-tensor theories with coupling between the scalar and the Gauss-Bonnet invariant that exhibit spontaneous scalarization for both black holes and compact stars. In particular, these theories formally admit all of the stationary solutions of general relativity, but these are not dynamically preferred if certain conditions are satisfied. Remarkably, black holes exhibit scalarization if their mass lies within one of many narrow bands. We find evidence that scalarization can occur in neutron stars as well.

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Hector O. Silva, Jeremy Sakstein, Leonardo Gualtieri, Thomas P. Sotiriou, Emanuele Berti. 2017-11-06. Spontaneous scalarization of black holes and compact stars from a Gauss-Bonnet coupling. https://doi.org/10.1103/physrevlett.120.131104

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