Thin accretion disks and charged rotating dilaton black holes

Abstract

Einstein-Maxwell-dilaton theory is an interesting theory of gravity for studying scalar fields in the context of no-hair theorem. In this work, we consider static charged dilaton and charged, slowly rotating dilaton black holes in Einstein-Maxwell-dilaton gravity. We investigate the accretion process in thin disks around such black holes, using the Novikov-Thorne model. The electromagnetic flux, temperature distribution, energy conversion efficiency and also innermost stable circular orbits of thin disks are obtained and effects of dilaton and rotation parameters are studied. For the static and slowly rotating black holes the results are compared to that of Schwarzschild and Kerr, respectively.

Thin accretion disks around rotating black holes in 4D Einstein–Gauss–Bonnet gravity

“…In this analysis the radiative efficiency, in the sense of the capability of the central compact object to convert rest mass into outgoing radiation via the accretion process, was also computed. Thin accretion disk properties in modified theories of gravity such as f (R) gravity [5][6][7], scalar-tensor-vector gravity [8], Einstein-Maxwelldilaton theory [9,10], Einstein-scalar-Gauss-Bonnet gravity [11,12], Chern-Simons [13] and Horava-Lifshitz [14] gravity have been studied in the past. In higher-dimensional gravity models such as Kaluza-Klein and brane-world models, thin accretion disks have been investigated in [15][16][17].…”

“…For instance, charged and rotating 4D EGB BH solutions [42][43][44], BH solutions in Lovelock gravity [45,46], BH solutions surrounded by clouds of strings [47], Bardeen BHs [48], Hayward BHs [49], spherically symmetric and thin shell wormhole solutions [50,51] and relativistic stars [52] have been extensively studied. Also, a large number of interesting aspects of the theory including geodesic motion and shadow [53][54][55][56], strong and weak gravitational lensing [57][58][59][60], quasinormal modes of BHs [61][62][63][64][65], instability of (A)dS BHs [66][67][68], thermodynamics and phase transition [69][70][71][72], Hawking radiation [73,74] and new quark stars [75,76] have also been stud-ied. For further references on 4D EGB gravity see [77][78][79][80][81][82][83][84][85][86][87]…”

Motion of particles and gravitational lensing around the (2+1)-dimensional BTZ black hole in Gauss–Bonnet gravity

“…The thermodynamics, phase transition and Joule-Thomson expansion of a 4D Gauss-Bonnet AdS black hole [25], particle acceleration [26], thermodynamic geometry of the 4D EGB AdS black hole [27], the emergent universe scenario in 4D EGB gravity [28], the extended thermodynamics and microstructures of a 4D charged EGB black hole [29], the shadow of a rotating 4D EGB black hole [30] and gravitational lensing of a 4D EGB black hole [31,32] have been widely studied in the literature.…”

Embedding Gauss–Bonnet Scalarization Models in Higher Dimensional Topological Theories

“…Further work includes the study of scalarized BHs in various extensions of the initial framework [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] and the investigation of solutions' stability [25][26][27][28]; furthermore, partial analytical results are reported in Refs. [29][30][31][32], while scalarized, rotating BHs are studied in [33][34][35][36][37][38][39].…”