Upper bound on the radius of the innermost photonsphere in the regular compact star spacetime

Guohua Liu; Yan Peng

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arXiv · 2402.15517

Upper bound on the radius of the innermost photonsphere in the regular compact star spacetime

Guohua Liu·Yan Peng

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Abstract

We study properties of the innermost photonsphere in the regular compact star background. We take the traceless energy-momentum tensor and dominant energy conditions. In the regular compact star background, we analytically obtain an upper bound on the radius of the innermost photonsphere as $r_{\gamma}^{in}\leqslant \frac{12}{5}M$, where $r_{\gamma}^{in}$ is the radius of the innermost photonsphere and $M$ is the total ADM mass of the asymptotically flat compact star spacetime.

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Guohua Liu, Yan Peng. 2024-02-09. Upper bound on the radius of the innermost photonsphere in the regular compact star spacetime. https://arxiv.org/abs/2402.15517

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