Lorentz Invariance Violation induced time delays in GRBs in different cosmological models

TL;DR

This study investigates energy-dependent time delays in gamma-ray bursts caused by Lorentz Invariance Violation across various cosmological models, finding the effect persists beyond the standard model and is most pronounced in certain dark energy scenarios.

Contribution

It extends previous LIV analysis by exploring multiple alternative cosmological models, revealing the robustness of LIV effects beyond the standard cosmology.

Findings

LIV-induced time delays are present in all considered models.

The effect is strongest in quintessence with variable equation of state.

Results suggest LIV effects are not exclusive to standard cosmology.

Abstract

Lorentz Invariance Violation (LIV) manifesting itself by energy dependent modification of standard relativistic dispersion relation has recently attracted a considerable attention. Ellis et al. previously investigated the energy dependent time offsets in different energy bands on a sample of gamma ray bursts and, assuming standard cosmological model, they found a weak indication for redshift dependence of time delays suggestive of LIV. Going beyond the $\Lambda$CDM cosmology we extend this analysis considering also four alternative models of dark energy (quintessence with constant and variable equation of state, Chaplygin gas and brane-world cosmology). It turns out that the effect noticed by Ellis et al. is also present in those models and is the strongest for quintessence with variable equation of state.