Bardeen Black Holes in the Regularized $4D$ Einstein--Gauss--Bonnet Gravity

Abstract

In this paper, following the idea of Glavan and Lin [Phys. Rev. Lett. 124, 081301 (2020)] of rescaling the Gauss-Bonnet (GB) coupling constant to α/(D − 4), we obtain the Bardeen black hole solution of 4D Einstein-Gauss-Bonnet gravity. We analyze the horizon structure to determine the effect of GB parameter α on the minimum and maximum cutoff values of mass, M 0 , and magnetic monopole charge, g 0 , for the existence of a black hole horizon. The analytical expressions for thermodynamical quantities, namely Hawking temperature T + , entropy S + , Gibbs free energy F + and specific heat C + associated with the black hole horizon are determined. In the analysis of heat capacity, we find that there exists a critical value of horizon radius, r c + , corresponding to the local maximum of Hawking temperature, at which heat capacity diverges, confirming the second-order phase transition.

Einstein Gauss-Bonnet Theories as Ordinary, Wess-Zumino Conformal Anomaly Actions

“…A nonlocal EGB theory of gravity follows quite directly from this action, once we add to (27) the EH term. As clear from (25), the dilaton φ is removed by solving that equation by the Green function of ∆ 4 .…”

Null geodesics and shadow of 4$D$ Einstein-Gauss-Bonnet black holes surrounded by quintessence

“…It is worth mentioning that these consistent theories share the black hole solutions with the original 4D EGB gravity that attracted a great deal of attention. For instance, the black hole solutions [103]- [111], quasinormal modes and stability analysis of black holes [112]- [118], thermodynamics and weak cosmic censorship [119]- [122], thin accretion disks [123]- [124], test particle motion and black hole shadow [125]- [131], gravitational lensing [132]- [135] and also some cosmological aspects of 4D EGB gravity [136]- [141] have been extensively studied. In this paper, we consider 4D EGB black holes surrounded by quintessence matter [142] to study the null geodesics around them and investigate the effects of the model parameters on these trajectories.…”

$P-V$ criticality and Joule-Thomson Expansion of Hayward-AdS black holes in 4D Einstein-Gauss-Bonnet gravity

“…Furthermore, the spherically symmetric black hole solutions have been also constructed in this paper. The generalization to other black holes has also appeared, for instance the charged AdS case [8], Lovelock [9,10], rotating [11,12], Born-Infeld [13], Bardeen [14] Hayward [15], etc. There also some important properties of the related 4D EGB black holes have been studied, such as the spinning test particle in the black hole [16], the causality [17], the stability and shadows [18,19].…”