Optical and thermodynamic behaviors of Ayón–Beato–García black holes for 4D Einstein Gauss–Bonnet gravity

Dyonic Ads Black Holes with Quasi-Topological Electromagnetism in $4\-D$ Einstein Gauss-Bonnet Gravity

“…In this regard, a recent observation was made with the goal of revealing the first image of a black hole, namely the M87* image [4][5][6][7][8][9], invented by EHT collaboration. Following up on this observation provides a great opportunity to compare a large variety of black holes with respect to size and shape associated with shadow behaviors with those of M87* [43][44][45][46][47]. Furthermore, another activity serves to discover the hidden mechanism of the black hole in a way that its background geometry is externally perturbed, providing the so-called quasinormal modes.…”

“…The theory has all of the components of general relativity and avoids the Lovelock theorem regarding quadratic supplemented terms in 4D space-time. The latest activities come up with the essence of 4D EGB gravity, like shadow behaviors [35,36,41,42] and thermodynamics [32,33,35,[43][44][45][46][47]. However, in Ref.s [55][56][57], it has been argued that choosing D = 4, leads to an ill defined theory and can have several conceptual issues.…”

Joule‐Thomson Expansion and Optical Behaviour of Reissner‐Nordström‐Anti‐de Sitter Black Holes in Rastall Gravity Surrounded by a Quintessence Field

“…Showing the optical behaviour pertinent to our black hole solution is the primary objective of this section. Well, taking advantage of many works regarding shadow behaviours [ 30,31 ] helps us discover in an easy way a one‐dimensional closed curve on the image plane. Indeed, an examination of the optical aspect, particularly the shadow image, arises from considering the Hamilton‐Jacobi action [ 32,33 ] $$$$\begin{equation} \frac{\partial \mathcal {S}}{\partial \delta }+H=0, \end{equation}$$$$where $$\mathcal {S}$$ and δ are the Jacobi action and the affine parameter along the geodesics, respectively.…”

“…Showing the optical behaviour pertinent to our black hole solution is the primary objective of this section. Well, taking advantage of many works regarding shadow behaviours [30,31] helps us discover in an easy way a one-dimensional closed curve on the image plane. Indeed, an examination of the optical aspect, particularly the shadow image, arises from considering the Hamilton-Jacobi action [32,33] 𝜕 𝜕𝛿…”

$${\textbf{D}}$$-dimensional dyonic AdS black holes with quasi-topological electromagnetism in Einstein Gauss–Bonnet gravity

“…Recent observations have managed to show, with the help of informatics data, a simulated image with regard to black objects. Roughly speaking, the M87* picture [34,35], yielded an intensive study of the black hole shadow in different gravity models [36][37][38][39][40][41][42][43].…”