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arXiv · 2608.02736

Novel Observable Signals from First-Order Gravitational Phase Transitions

Murat Özinan·Oğuzhan K. Yamak·Fethi M. Ramazanoğlu
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Abstract

Spontaneous scalarization is a well-known phenomenon in scalar-tensor theories, featuring large deviations from general relativity. However, some of its signatures are hard to detect, because it is generally studied as a continuous phase transition. We show that scalarization occurs in a discontinuous (first-order) manner in many astrophysically relevant scenarios. This leads to loud signals that provide new tests of gravity. We demonstrate this in the case of gravitational wave breathing modes from a neutron star that scalarizes due to accretion, and discuss other possibilities.

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Murat Özinan, Oğuzhan K. Yamak, Fethi M. Ramazanoğlu. 2026-08-03. Novel Observable Signals from First-Order Gravitational Phase Transitions. https://arxiv.org/abs/2608.02736

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