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arXiv · 2410.14108

Neutron stars in Gauss-Bonnet extended Starobinsky gravity

Zhonghai Liu·Ziyi Li·Liang Liang·Shoulong Li·Hongwei Yu
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Abstract

Recently, a class of Gauss-Bonnet extended Starobinsky gravity was proposed, allowing black holes to carry ghost-free massive scalar hair for the first time without requiring additional matter fields. This intriguing feature offers a new perspective for understanding higher-curvature pure gravity and highlights the importance of further studying the potential effects of Gauss-Bonnet extensions in gravitational systems beyond black holes. In this study, we investigate the properties of neutron stars within this model, focusing on how the higher-curvature terms, particularly the coupling between the Gauss-Bonnet term and the curvature-squared term, impact the stellar structure. We present a detailed analysis of these effects and compute the moment of inertia for rotating neutron stars under the slow-rotation approximation. The substantial differences in the moment of inertia between general relativity and Gauss-Bonnet extended Starobinsky gravity are expected to be detectable through future high-precision observations.

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Zhonghai Liu, Ziyi Li, Liang Liang, Shoulong Li, Hongwei Yu. 2024-10-18. Neutron stars in Gauss-Bonnet extended Starobinsky gravity. https://arxiv.org/abs/2410.14108

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