Gravitational Perturbation in Nonlocal Modified Tolman VII Model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Jayawiguna, Byon N., Burikham, Piyabut
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929195284692992
author Jayawiguna, Byon N.
Burikham, Piyabut
author_facet Jayawiguna, Byon N.
Burikham, Piyabut
contents In comparison to the original Tolman VII model, Exact Modified Tolman VII (EMTVII) with one additional parameter can increase the compactness of compact object. When the compactness is in the ultracompact regime, the quasinormal modes~(QNMs) of the trapped mode as well as the gravitational echoes become more viable. Starting with the EMTVII model, we introduce nonlocality into the matter sector and analyze the effective potential, the QNMs, and the gravitational echoes of the compact and ultracompact object in the nonlocal model. The nonlocal gravity version of EMTVII~(NEMTVII) is parametrized by the nonlocal parameter~($ β$), modified Tolman VII parameter ($ α$), and the compactness ($ \mathcal{C}$). It is found that the nonlocal profile produces the smeared surface and consequently reduce the compactness. The maximum compactness $\mathcal{C}_{max}=0.4$ occurs when $α=0=β$, i.e., EMTVII with no smearing. For relatively small value of $β= 0.01$ and the compactness $ \mathcal{C} \lesssim 0.2667$~(with $M=2.14$ solar masses, $R=11.835$ km at $α=1.4$), the causality condition and the dominant energy condition~(DEC) are satisfied. The quasinormal modes of the gravitational perturbation are calculated using Bohr-Sommerfeld (BS) fitting and we find that the nonlocality produces less trapped modes than the original (EMTVII) counterpart. At high compactness, gravitational echoes are simulated numerically. Echoes are found to exist in the parameter space where the dominant energy condition and the causality condition are violated.
format Preprint
id arxiv_https___arxiv_org_abs_2304_14035
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Gravitational Perturbation in Nonlocal Modified Tolman VII Model
Jayawiguna, Byon N.
Burikham, Piyabut
General Relativity and Quantum Cosmology
In comparison to the original Tolman VII model, Exact Modified Tolman VII (EMTVII) with one additional parameter can increase the compactness of compact object. When the compactness is in the ultracompact regime, the quasinormal modes~(QNMs) of the trapped mode as well as the gravitational echoes become more viable. Starting with the EMTVII model, we introduce nonlocality into the matter sector and analyze the effective potential, the QNMs, and the gravitational echoes of the compact and ultracompact object in the nonlocal model. The nonlocal gravity version of EMTVII~(NEMTVII) is parametrized by the nonlocal parameter~($ β$), modified Tolman VII parameter ($ α$), and the compactness ($ \mathcal{C}$). It is found that the nonlocal profile produces the smeared surface and consequently reduce the compactness. The maximum compactness $\mathcal{C}_{max}=0.4$ occurs when $α=0=β$, i.e., EMTVII with no smearing. For relatively small value of $β= 0.01$ and the compactness $ \mathcal{C} \lesssim 0.2667$~(with $M=2.14$ solar masses, $R=11.835$ km at $α=1.4$), the causality condition and the dominant energy condition~(DEC) are satisfied. The quasinormal modes of the gravitational perturbation are calculated using Bohr-Sommerfeld (BS) fitting and we find that the nonlocality produces less trapped modes than the original (EMTVII) counterpart. At high compactness, gravitational echoes are simulated numerically. Echoes are found to exist in the parameter space where the dominant energy condition and the causality condition are violated.
title Gravitational Perturbation in Nonlocal Modified Tolman VII Model
topic General Relativity and Quantum Cosmology
url https://arxiv.org/abs/2304.14035