http://arxiv.org/abs/2210.14025
Gravitational waves from compact binary coalescence are valuable for testing theories of gravity in the strong field regime. By measuring neutron star tidal deformability in gravitational waves from binary neutron stars, stringent constraints were placed on the equation of state of matter at extreme densities. Tidal Love numbers in alternative theories of gravity may differ significantly from their general relativistic counterparts. Understanding exactly how the tidal Love numbers change will enable scientists to untangle effects from physics beyond general relativity from the uncertainty in the equation of state measurement. In this work, we explicitly calculate the fully relativistic $l \geq 2$ tidal love numbers for neutron stars in scalar-tensor theories of gravitation. We use several realistic equations of state to explore how the mass, radius, and tidal deformability relations differ from those of general relativity. We find that tidal Love numbers and tidal deformabilities can differ significantly from those in general relativity ( $>200\%$ in strong scalarization cases) in certain regimes. This difference suggests that using the tidal Love numbers from general relativity could lead to significant errors in tests of general relativity using the gravitational waves from binary neutron star and neutron star-black hole mergers.
S. Brown
Wed, 26 Oct 22
50/73
Comments: Planned for submission to APJ