Superentropic AdS Black Hole Shadows

Abstract

We study shadow aspects of superentropic black holes in four dimensions. Using Hamilton-Jacobi formalism, we first get the null geodesic equations. In the celestial coordinate framework relying on fixed positions of observers, we investigate the shadow behaviors in terms of the mass and the cosmological scale variation parameters. Among others, we obtain ellipse shaped geometries contrary to usual black hole solutions. Modifying the ordinary relations describing geometrical observables, we discuss the size and the shape deformation parameters of these non-trivial geometric forms. Due to horizonless limits associated with certain mass values, we explore the shadow of the naked singularity of such black holes.

Superentropic Black Hole Shadows in Arbitrary Dimensions

“…At this level, it is interesting to comment these equations. Taking ψ i = 0, we recover the four dimensional geodesic equations reported in [14]. The functions Ψ i (ψ i ) and ∆ share data on thel shadow behaviors in higher dimensions.…”

“…It is worth noting that the variables ψ i and the functions S ψ i (ψ i ) are associated with the extra dimensions. Sending these extra dimensional functions to zero, we recover the expressions of the four dimensional action reported in [14]. Using the separation method and the Carter constant, we can get the complete null geodesic equations.…”

“…Moreover, the optical aspect has been approached by investigating the deflection angle of light rays and the shadow behaviors [9][10][11][12][13]. In four dimensions, the black hole shadows of various black holes have been engineered using one dimensional real curves [14][15][16][17]. In particular, the visualization of the shadow casts are obtained from the null geodesic equations.…”

“…It has been remarked that the associated size can be controlled by internal and external moduli spaces including the dark field sector [10]. The circular geometric manifestation can be distorted by introducing the rotating parameter which generates nontrivial geometries involving either D or cardioid shapes [14,15,[17][18][19][20]. The latter has been appeared in the study of AdS black holes obtained from type superstrings and Mtheory scenarios using brane physics [19,21].…”

“…Precisely, the thermodynamic behaviors of such black holes have been examined by exploiting ultraspinning approximation limits [30,31]. Concerning the optical aspect, the four dimensional shadows have been studied using the Hamilton-Jacobi formalism [14]. Among others, it has been found many geometrical configurations including ellipse shaped and naked singularity behaviors.…”