Energetics and optical properties of 6-dimensional rotating black hole in pure Gauss–Bonnet gravity

Abstract

We study physical processes around a rotating black hole in pure Gauss-Bonnet (GB) gravity. In pure GB gravity, the gravitational potential has a slower fall-off as compared to the corresponding Einstein potential in the same dimension. It is therefore expected that the energetics of a pure GB black hole would be weaker, and our analysis bears out that the efficiency of energy extraction by the Penroseprocess is increased to 25.8 % and the particle acceleration is increased to 55.28 %; the optical shadow of the black hole is decreased. These are in principle distinguishing observable features of a pure GB black hole.

Horizon structure of rotating Einstein–Born–Infeld black holes and shadow

“…a dark area in front of a luminous background [56,59]. Hence, their is a significant effort to study black hole shadows and this has become a quite active research field [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48] (for a review, see [60]). For the Schwarzschild black hole the shadow of the black hole is a perfect circle [60], and it is enlarged in the case of a Reissner-Nordström black hole [61].…”

“…The photons that cross the event horizon, due to strong gravity, are removed from the observable universe which lead to a shadow (silhouette) imprinted by a black hole on the bright emission that exists in its vicinity. So far the shadows of the compact gravitational objects in the different cases have been extensively studied, see, e.g., [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48]. Furthermore a new general formalism to describe the shadow of black hole as an arbitrary polar curve expressed in terms of a Legendre expansion was developed in a recent paper [49].…”

Fifty Years of Energy Extraction from Rotating Black Hole: Revisiting Magnetic Penrose Process

“…Using Equations (38) and (39) at the point of split, the general expression for the efficiency reads…”

Optical and thermodynamic properties of a rotating dyonic black hole spacetime in $${\mathcal {N}} = 2, U(1)^2$$ gauged supergravity

“…The study of phenomenon for BH shadow can provide the useful information about the various physical aspects of any given BH spacetime and the recent image from Event Horizon Telescope (EHT) [15][16][17][18][19][20] marks a significant mile stone in the study of BH physics. The mathematical aspect of the very phenomenon which has been developed over the year [21][22][23][24][25][26][27][28][29][30][31][32][33][34][35] can be studied with observed data which can further help to hone the mathematical models of the extraordinary astronomical objects like a BH. Based on such standpoints, we are motivated to study the motion of photons in ADS geometry to observe the effect of different charges on the path of the light along with the shadows and the relation for distance of closest approach with the magnetic charges (v), the gauge coupling constant (g) and NUT charge (N g ).…”