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arXiv · 2608.12992

Temperature effects on white dwarfs in modified gravity

Sofía Vidal·Aneta Wojnar·Laur Järv
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Abstract

In this article we analyze the effects of a finite temperature equation of state on the equilibrium structure of white dwarfs in massive Brans-Dicke theory as well as the symmetron and dilaton screening mechanisms. We compute and present the numerically obtained mass-radius relation, effective gravitational constant as well as radial profiles of the scalar field, pressure and metric within the star. We show that assuming a non-zero temperature effectively results in a larger radius while leaving the total mass of the star essentially unchanged, and discuss the interplay between the effective gravitational constant, central density, and radius of the star.

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Sofía Vidal, Aneta Wojnar, Laur Järv. 2026-08-13. Temperature effects on white dwarfs in modified gravity. https://arxiv.org/abs/2608.12992

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