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arXiv · 1805.08976

Sine-Gordon solitonic scalar stars and black holes

Edgardo Franzin·Mariano Cadoni·Matteo Tuveri
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Abstract

We study exact, analytic, static, spherically symmetric, four-dimensional solutions of minimally coupled Einstein-scalar gravity, sourced by a scalar field whose profile has the form of the sine-Gordon soliton. We present a horizonless, everywhere regular and positive-mass solution (a solitonic star) and a black hole. The scalar potential behaves as a constant near the origin and vanishes at infinity. In particular, the solitonic scalar star interpolates between an anti-de Sitter and an asympototically flat spacetime. The black-hole spacetime is unstable against linear perturbations, while due to numerical issues, we were not able to determine with confidence whether or not the star-like background solution is stable.

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Edgardo Franzin, Mariano Cadoni, Matteo Tuveri. 2018-06-06. Sine-Gordon solitonic scalar stars and black holes. https://doi.org/10.1103/physrevd.97.124018

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