Exact Gravastar Solution

Farook Rahaman; Bikramarka S. Choudhury; Aritra Sanyal; Anikul Islam; Bidisha Samanta

doi:10.1016/j.physletb.2026.140412

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arXiv · 2604.09719

Exact Gravastar Solution

Farook Rahaman·Bikramarka S. Choudhury·Aritra Sanyal·Anikul Islam·Bidisha Samanta

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Abstract

Astrophysical black holes arise as exact solutions of the Einstein field equations. Therefore, any alternative, such as a gravastar, must satisfy the same level of mathematical rigor and internal consistency. A physically viable gravastar model should not rely on approximations or ad hoc matching of regions, but instead provide a single, exact, and self-consistent solution of the Einstein field equations throughout the entire spacetime. In this work, we propose an exact solution to the Einstein field equations in the context of gravitational vacuum stars (gravastars), originally introduced by Mazur and Mottola. This framework presents an alternative end state of gravitational collapse, leading to the formation of a compact object distinct from a classical black hole. Our model is constructed by dividing the gravastar into three regions, each described by exact solutions of the Einstein field equations. We analyze the key physical properties of the resulting configuration and examine its theoretical consistency and astrophysical viability. This study provides a clear and systematic assessment of gravastars as potential alternatives to black holes.

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Farook Rahaman, Bikramarka S. Choudhury, Aritra Sanyal, Anikul Islam, Bidisha Samanta. 2026-04-08. Exact Gravastar Solution. https://doi.org/10.1016/j.physletb.2026.140412

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