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arXiv · 2006.07652

Quark stars with isotropic matter in Hořava gravity and Einstein-æther theory

Grigoris Panotopoulos·Daniele Vernieri·Ilídio Lopes
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Abstract

We study non-rotating and isotropic strange quark stars in Lorentz-violating theories of gravity, and in particular in Hořava gravity and Einstein-æther theory. For quark matter we adopt both linear and non-linear equations of state, corresponding to the MIT bag model and colour flavour locked state, respectively. The new structure equations describing hydrostatic equilibrium generalize the usual Tolman-Oppenheimer-Volkoff (TOV) equations of Einstein's general relativity. A dimensionless parameter $ν$ measures the deviation from the standard TOV equations, which are recovered in the limit $ν\rightarrow 0$. We compute the mass, the radius as well as the compactness of the stars, and we show graphically the impact of the parameter $ν$ on the mass-to-radius profiles for different equations of state describing quark matter. The energy conditions and stability criteria are also considered, and they are all found to be fulfilled.

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Grigoris Panotopoulos, Daniele Vernieri, Ilídio Lopes. 2020-06-13. Quark stars with isotropic matter in Hořava gravity and Einstein-æther theory. https://doi.org/10.1140/epjc%2Fs10052-020-8105-5

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