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arXiv · 2509.05202

Phase transitions of boson stars in scalar-tensor theories

Hyat Huang·Burkhard Kleihaus·Jutta Kunz·Meng-Yun Lai·Eugen Radu·De-Cheng Zou
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Abstract

In scalar-tensor theories, compact objects may experience spontaneous scalarization. Recently, it was shown that matter-induced spontaneous scalarization of neutron stars is predominantly associated with a first-order phase transition. Here we consider matter-induced spontaneous scalarization of boson stars. Employing a repulsive quartic potential for the bosonic matter, we find only first-order phase transitions.

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Hyat Huang, Burkhard Kleihaus, Jutta Kunz, Meng-Yun Lai, Eugen Radu, De-Cheng Zou. 2025-09-05. Phase transitions of boson stars in scalar-tensor theories. https://doi.org/10.1103/8l73-dxxd

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