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arXiv · 2505.20886

Slowly Rotating and Tidal Deformation of Nonlocal Modified Tolman VII Star

Byon N. Jayawiguna·Piyabut Burikham
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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~$( \lambda_{\textrm{tid}} )$ 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~$( \bar{\lambda}_{\textrm{rot}} )$, 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.

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Byon N. Jayawiguna, Piyabut Burikham. 2025-05-27. Slowly Rotating and Tidal Deformation of Nonlocal Modified Tolman VII Star. https://arxiv.org/abs/2505.20886

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