Extremely small stars in scalar-tensor gravity: when stellar radius is less than Schwarzschild one

We show analytically that there exist compact stellar objects akin to neutron stars whose radius is smaller than the Schwarzschild radius defined by Arnowitt-Deser-Misner (ADM) mass. The radius of the compact object is defined by the radius where the energy density and the pressure of ordinary matte...

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Detalles Bibliográficos
Autores: Nojiri, Shin'ichi, Odintsov, Sergei D., Sedrakian, Armen
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/382105
Acceso en línea:http://hdl.handle.net/10261/382105
http://arxiv.org/abs/2312.15839v2
Access Level:acceso abierto
Palabra clave:General relativity and quantum cosmology
Descripción
Sumario:We show analytically that there exist compact stellar objects akin to neutron stars whose radius is smaller than the Schwarzschild radius defined by Arnowitt-Deser-Misner (ADM) mass. The radius of the compact object is defined by the radius where the energy density and the pressure of ordinary matter vanish, while clouds of scalar(s) can extend beyond this radius – a situation that is often encountered in modified gravity theories, like gravity and the scalar–Einstein–Gauss-Bonnet gravity. The clouds of scalar mode(s) give additional contributions to the ADM mass and as a result, the corresponding Schwarzschild radius given by the ADM mass can be larger than that of the compact object.