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arXiv · 2107.03859

Five-dimensional compact stars in Einstein-Gauss-Bonnet gravity

Juan M. Z. Pretel·Ayan Banerjee·Anirudh Pradhan
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Abstract

Within the framework of Einstein-Gauss-Bonnet theory in five-dimensional spacetime ($5D$ EGB), we derive the hydrostatic equilibrium equations and solve them numerically to obtain neutron stars for both isotropic and anisotropic distribution of matter. The mass-radius relations are obtained for SLy equation of state, which describes both the solid crust and the liquid core of neutron stars, and for a wide range of the Gauss-Bonnet coupling parameter $α$. More specifically, we find that the contribution of the Gauss-Bonnet term leads to substantial deviations from Einstein gravity. We also discuss that after a certain value of $α$, the theory admits higher maximum masses compared with general relativity, however, the causality condition is violated in the high-mass region. Finally, our results are compared with the recent observations data on mass-radius diagram.

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Juan M. Z. Pretel, Ayan Banerjee, Anirudh Pradhan. 2024-09-25. Five-dimensional compact stars in Einstein-Gauss-Bonnet gravity. https://doi.org/10.1016/j.nuclphysb.2024.116702

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