Spontaneous scalarization around a black hole in a dark matter halo

M. Navid Gasemi Zad; H. Mohseni Sadjadi

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arXiv · 2607.17367

Spontaneous scalarization around a black hole in a dark matter halo

M. Navid Gasemi Zad·H. Mohseni Sadjadi

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Abstract

We demonstrate that in a scalar-tensor theory where dark matter is conformally coupled to a scalar field, a black hole surrounded by a Hernquist dark matter halo can undergo spontaneous scalarization, acquiring a nontrivial scalar field configuration. The astrophysical properties of the dark matter halo directly dictate the quantum-like spectrum of scalar field configurations around the central black hole. Remarkably, the conformal coupling constant becomes discretized and is determined solely by the halo's compactness parameter.

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M. Navid Gasemi Zad, H. Mohseni Sadjadi. 2026-07-19. Spontaneous scalarization around a black hole in a dark matter halo. https://arxiv.org/abs/2607.17367

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