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arXiv · 2311.02915

Electromagnetic extension of Buchdahl bound in $f(R,T)$ gravity

Soumik Bhattacharya·Ranjan Sharma·Sunil D. Maharaj
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Abstract

We develop a static charged stellar model in $f(R,T)$ gravity where the modification is assumed to be linear in $T$ which is the trace of the energy momentum tensor. The exterior spacetime of the charged object is described by the Reissner-Nordstr\"om metric. The interior solution is obtained by invoking the Buchdahl-Vaidya-Tikekar ansatz, for the metric potential $g_{rr}$, which has a clear geometric interpretation. A detailed physical analysis of the model clearly shows distinct physical features of the resulting stellar configuration under such a modification. We find the maximum compactness bound for such a class of compact stars which is a generalization of the Buchdahl bound for a charged sphere described in $f(R,T)$ gravity. Our result shows physical behaviour that is distinct from general relativity.

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Soumik Bhattacharya, Ranjan Sharma, Sunil D. Maharaj. 2023-11-06. Electromagnetic extension of Buchdahl bound in $f(R,T)$ gravity. https://arxiv.org/abs/2311.02915

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