Strange Quark Stars in 4D Einstein-Gauss-Bonnet Gravity

TL;DR

This paper explores the theoretical construction of strange stars within the framework of 4D Einstein-Gauss-Bonnet gravity, analyzing their properties and stability using numerical solutions to modified TOV equations.

Contribution

It introduces a regularized 4D Einstein-Gauss-Bonnet gravity model and applies it to model strange stars, comparing results with standard General Relativity.

Findings

The coupling constant $eta$ significantly affects star properties.

Strange stars in 4D EGB gravity can achieve higher compactness.

Stability criteria are consistent with observational constraints.

Abstract

The existence of strange matter in compact stars may pose striking sequels of the various physical phenomena. As an alternative to neutron stars, a new class of compact stars called strange stars should exist if the strange matter hypothesis is true. In the present article, we investigate the possible construction of the strange stars in quark matter phases based on the MIT bag model. We consider scenarios in which strange stars have no crusts. Then we apply two types of equations of state to quantify the mass-radius diagram for static strange star models performing the numerical calculation to the modified Tolman-Oppenheimer-Volkoff (TOV) equations in the context of $4D$ Einstein-Gauss-Bonnet gravity. It is worth noting that the GB term gives rise to a non-trivial contribution to the gravitational dynamics in the limit $D \to 4$. However, the claim that the resulting theory is of pure graviton was cast in doubt by several grounds. Thus, we begin our discussion with showing the regularized $4D$ EGB theory has an equivalent action as the novel $4D$ EGB in a spherically symmetric spacetime. We also study the effects of coupling constant $\alpha$ on the physical properties of the constructed strange stars including the compactness and criterion of adiabatic stability. Finally, we compare our results to those obtained from the standard GR.