The Remnant of GW170817: A Trapped Neutron Star with a Massive Incompressible Superfluid Core

Abstract

Our bimetric spacetime model of glitching pulsars is applied to the remnant of GW170817. Accordingly, pulsars are born with embryonic incompressible superconducting gluon-quark superfluid cores (SuSu-matter) that are embedded in Minkowski spacetime, whereas the ambient compressible and dissipative media (CDM) are imbedded in curved spacetime. As pulsars cool down, the equilibrium between both spacetime is altered, thereby triggering the well-observed glitch phenomena. Based thereon and assuming all neutron stars (NSs) to be born with the same initial mass of $M_{NS}(t=0) \approx 1.25 \MSun,$ we argue that the remnant of GW170817 should be a relatively faint NS with a hypermassive central core made of SuSu-matter. The effective mass and radius of the remnant are predicted to be $\mathcal{M}_{tot}=3.351 \MSun$ and $R_{rem}=10.764$ km, whereas the mass of the enclosed SuSu-core is $\mathcal{M}_{core}=1.7 \MSun.$ Here, about $1/2~ \mathcal{M}_{core}$ is an energy enhancement triggered by the phase transition of the gluon-quark-plasma from the microscopic into macroscopic scale. The current compactness of the remnant is $\alpha_c = 0.918,$ but predicted to increase as the CDM cool down to finally turn the remnant invisible and therefore to an excellent black hole candidate.