Neutron stars and the secret lives of quarks

Jeffrey M. Berryman, Susan Gardner.


The discovery of non-diffuse sources of gravitational waves through compact-object mergers opens new prospects for the study of physics beyond the Standard Model. In this Letter, we consider the implications of the observation of GW190814, involving a coalescence of a black hole with a \sim2.6 M_\odot compact object, which may be too massive to be a neutron star, given our current knowledge of the nuclear matter equation of state. We consider the possibility of a new force between quarks, suggested in other contexts, that modifies the neutron star equation of state, particularly at supranuclear densities. We evaluate how this modification can impact a neutron star’s mass and radius to make the observed heavy compact object more probably a neutron star, rather than a black hole, and suggest that further such objects may yet be found. We note the terrestrial and astrophysical measurements that could confirm our picture.

Associated Fellows