Stable and self-consistent compact star models in teleparallel gravity

• Published in: The European physical journal. C, Particles and fields Vol. 80; no. 10; pp. 1 - 18
• Main Authors: Nashed, G. G. L., Capozziello, S.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-10-2020; Springer; Springer Nature B.V; SpringerOpen
• Subjects: Analysis; Anisotropy; Astronomy; Astrophysics and Cosmology; Boundary conditions; Elementary Particles; Gravitation; Hadrons; Heavy Ions; Measurement Science and Instrumentation; Model testing; Nuclear Energy; Nuclear Physics; Parameter estimation; Physics; Physics and Astronomy; Pulsars; Quantum Field Theories; Quantum Field Theory; Regular Article - Theoretical Physics; String Theory
• ISSN: 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-020-08551-1

In the framework of Teleparallel Gravity, we derive a charged non-vacuum solution for a physically symmetric tetrad field with two unknown functions of radial coordinate. The field equations result in a closed-form adopting particular metric potentials and a suitable anisotropy function combined with the charge. Under these circumstances, it is possible to obtain a set of configurations compatible with observed pulsars. Specifically, boundary conditions for the interior spacetime are applied to the exterior Reissner–Nordström metric to constrain the radial pressure that has to vanish through the boundary. Starting from these considerations, we are able to fix the model parameters. The pulsar
PSR J
1614
-
2230
, with estimated mass
M
=
1.97
±
0.04
M
⊚
,
and radius
R
=
9.69
±
0.2
km is used to test numerically the model. The stability is studied, through the causality conditions and adiabatic index, adopting the Tolman–Oppenheimer–Volkov equation. The mass–radius (
M
, 
R
) relation is derived. Furthermore, the compatibility of the model with other observed pulsars is also studied. We reasonably conclude that the model can represent realistic compact objects.