Static spherically symmetric threeform stars
Abstract
We consider interior static and spherically symmetric solutions in a gravity theory that extends the standard HilbertEinstein action with a Lagrangian constructed from a threeform field A_{α β γ}, which generates, via the field strength and a potential term, a new component in the total energymomentum tensor of the gravitational system. We formulate the field equations in Schwarzschild coordinates and investigate their solutions numerically for different equations of state of neutron and quark matter, by assuming that the threefield potential is either a constant or possesses a Higgslike form. Moreover, stellar models, described by the stifffluid, radiationlike, bag model and the BoseEinstein condensate equations of state are explicitly obtained in both general relativity and threeform gravity, thus allowing an indepth comparison between the astrophysical predictions of these two gravitational theories. As a general result we find that, for all the considered equations of state, threeform field stars are more massive than their general relativistic counterparts. As a possible astrophysical application, we suggest that the 2.5M_{⊙} mass compact object, associated with the GW190814 gravitational wave event, could be in fact a neutron or a quark star described by the threeform gravity theory.
 Publication:

European Physical Journal C
 Pub Date:
 April 2021
 DOI:
 10.1140/epjc/s10052021091059
 arXiv:
 arXiv:2101.04445
 Bibcode:
 2021EPJC...81..307B
 Keywords:

 General Relativity and Quantum Cosmology;
 Astrophysics  Solar and Stellar Astrophysics;
 High Energy Physics  Theory
 EPrint:
 23 pages, 24 figures