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arXiv · 2609.03237

Non-extensive entropy signatures in compact star

B. N. Jayawiguna·M. H. Al Ghifari·A. Rohim·A. Sulaksono
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Abstract

The non-extensive entropy models applied to the black-hole horizon are connected to the generalized Einstein--Hilbert action, $f(R)$, via the Wald entropy formalism. We demonstrate that quark star configurations characterized by the MIT bag model under this modified gravity approach conform to the observational lower and upper bounds established for compact objects linked to HESS J1731$-$347 and GW190814. Furthermore, we assess the effective energy conditions and corresponding speed of sound to evaluate the physical plausibility and stability of the stellar configurations. All non-extensive entropy models studied satisfied these conditions. Our findings show that the exotic compact objects offer a compelling and credible framework for exploring aspects of non-extensive entropy models, such as the Barrow, Tsallis-Cirto, and R\'enyi formalisms, and vice versa.

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B. N. Jayawiguna, M. H. Al Ghifari, A. Rohim, A. Sulaksono. 2026-09-03. Non-extensive entropy signatures in compact star. https://arxiv.org/abs/2609.03237

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