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arXiv · 1806.00568

Compactness of neutron stars and Tolman VII solutions in scalar-tensor gravity

Hajime Sotani·Kostas D. Kokkotas
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Abstract

We systematically examine the compactness of neutron stars as Tolman VII solutions in scalar-tensor theory of gravity. As a result, when the coupling constant is confined to values provided by astronomical observations we show that the maximum compactness of neutron stars in general relativity is higher than that in scalar-tensor gravity. In addition, we show that although ultra-compact stars, with radius smaller than the Regge-Wheeler potential peak, can exist in general relativity (e.g., Tolman VII solution), their scalarized counterparts cannot {be constructed} even in the limiting case of uniform density stars.

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Hajime Sotani, Kostas D. Kokkotas. 2018-06-02. Compactness of neutron stars and Tolman VII solutions in scalar-tensor gravity. https://doi.org/10.1103/physrevd.97.124034

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