Slowly Rotating and Tidal Deformation of Nonlocal Modified Tolman VII Star

Abstract

We investigate the moment of inertia, quadrupole deformation, and tidal deformation within the framework of nonlocal gravity, utilizing the exact modified Tolman-VII (NEMTVII) density model with an isotropic perfect fluid. The Love number~$(k_2)$ is derived using standard even-parity perturbation theory. Additionally, we explore the observational implications by analyzing the tidal deformability parameter~$({\lambda }_{\text{tid}})$ in comparison with the constraints from GW170817, GW190425, PSR J0348+0432, and PSR J0740+6620. We found that the results are consistent with the tidal constraint when $\alpha \gtrsim 1.6$ with the small $\beta$. For slowly rotating object, the dimensionless moment of inertia~$(\bar{I})$, rotational Love parameter~$({\bar{\lambda }}_{\text{rot}})$, and quadrupole moment~$(\bar{Q})$ are fully determined by the perturbed metric. Our findings reveal that the nonlocal parameter~$(\beta )$ significantly affects the star radius. For a fixed $\beta$ and varying $\alpha$, the $I$-Love-$Q$ relations are found to be universal. For varying $\beta$, the $I$-Love-$Q$ relations become non-universal.

Comments: 18 pages, 17 figures