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arXiv · 1905.12452

Anisotropic ultracompact Schwarzschild star by gravitational decoupling

J. Ovalle·C. Posada·Z. Stuchlík
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Abstract

We employ the minimal geometric deformation approach to gravitational decoupling (MGD-decoupling) in order to generate an exact anisotropic and non-uniform version of the ultracompact Schwarzschild star, or 'gravastar', proposed by Mazur and Mottola. This new system represents an ultracompact configuration of radius $R_{S}=2\cal{M}$ whose interior metric can be matched smoothly to a conformally deformed Schwarzschild exterior. Remarkably, the model satisfies some of the basic requirements to describe a stable stellar model, such as a positive density everywhere and decreasing monotonously from the centre, as well as a non-uniform and monotonic pressure.

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J. Ovalle, C. Posada, Z. Stuchlík. 2019-05-28. Anisotropic ultracompact Schwarzschild star by gravitational decoupling. https://doi.org/10.1088/1361-6382%2Fab4461

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