Thermodynamics of Einstein–Gauss–Bonnet black holes under the Generalized Uncertainty Principle Sasmita Kumari Pradhan, Jamima Gee Varghese, C. Fairoos International Journal of Modern Physics A, 2026 We explore the impact of the Generalized Uncertainty Principle (GUP) on the thermodynamics of five-dimensional Einstein–Gauss–Bonnet (EGB) black holes. A modified mass–temperature relation is derived under the assumption of local equilibrium, revealing that the black hole evolves into a stable remnant with a finite temperature, rather than undergoing complete evaporation. The modified entropy, obtained within this framework, deviates from the commonly expected logarithmic form. However, considering a linear GUP, which is obtained by combining Doubly Special Relativity (DSR) with the usual GUP, yields a logarithmic correction to the entropy similar to that of a five-dimensional Schwarzschild–Tangherlini black hole. However, the leading order term in the entropy of the EGB black hole is purely due to the underlying spacetime geometry, making the logarithmic term a higher order correction, unlike the case of the five-dimensional Schwarzschild black hole, where the leading order correction is logarithmic. Our results support the conjecture that the GUP-induced corrections to black hole entropy are sensitive to the dimensionality of spacetime.
Topological interpretation of black hole phase transition in Gauss-Bonnet gravity C. Fairoos International Journal of Modern Physics A, 2024 Phase transitions of Einstein–Gauss–Bonnet black holes are studied using Duan’s [Formula: see text]-field topological current theory, where black holes are treated as topological defects in the thermodynamic parameter space. The kinetics of thermodynamic defects are studied using Duan’s bifurcation theory. In this picture, a first-order phase transition between small/large black hole phases is interpreted as the interchange of winding numbers between the defects as a result of some action at a distance. We observe a first-order phase transition between small/large black holes for [Formula: see text] Einstein–Gauss–Bonnet theory similar to Reissner–Nordström black holes in AdS space. This implies that these black hole solutions share the same topology and phase structure. We have also studied the phase transition of neutral black holes in [Formula: see text] and found a transition between unstable small and large stable black hole phases similar to the case of neutral black holes in AdS space. Recently, it has been conjectured that black holes with similar topological structure exhibit the same thermodynamic properties. Our results strengthen the conjecture by connecting the topological nature of black holes to phase transitions.
Topological nature of black hole solutions in dRGT massive gravity C. Fairoos, T. Sharqui International Journal of Modern Physics A, 2023 We study the thermodynamic properties of black holes in dRGT massive gravity theory using Duan’s [Formula: see text] mapping topological current theory. The topological features and the corresponding thermodynamic stability conditions for neutral and charged cases are discussed. A neutral black hole in four dimensions has a topological number 0, sharing the same topological class of [Formula: see text] Gauss–Bonnet–AdS black hole. We show that the charged black hole in four-dimensional massive gravity has the same topological structure as the AdS-RN black hole. Further, we have extended the calculations to higher dimensions. Our calculations strengthen the conjecture that the addition of higher interaction terms to Einstein–Hilbert action does not alter the topological number of black holes in four space–time dimensions. However, in higher-dimensional massive gravity, the topological number indeed depends on the black hole parameters.
Overcharging higher curvature black holes Rajes Ghosh, C. Fairoos, Sudipta Sarkar Physical Review D, 2019 We examine the problem of overcharging extremal and near-extremal black hole solutions of Einstein-Gauss-Bonnet gravity in any dimension, generalizing the result in general relativity. We show that as in the case of general relativity, it is not possible to create a naked singularity by overcharging an extremal black hole in Einstein-Gauss-Bonnet gravity using a charged test particle. Our result suggests that the validity of the cosmic censorship hypothesis transcends beyond general relativity to well motivated higher curvature gravity.
Boundary conservation from bulk symmetry C. Fairoos, Avirup Ghosh, Sudipta Sarkar International Journal of Modern Physics D, 2018 The evolution of the black-hole horizon can be effectively captured by a fictitious membrane fluid living on the stretched horizon. We show that the dynamics of this boundary matter arises from the invariance of the bulk action under local symmetries in the presence of the inner boundary. If general covariance is broken in a semi-classical treatment of a quantum field near a black-hole horizon, we argue that it can be restored by the inclusion of a quantum flux into the membrane conservation equation which is exactly equal to the Hawking flux.
Black hole entropy production and transport coefficients in Lovelock gravity C. Fairoos, Avirup Ghosh, Sudipta Sarkar Physical Review D, 2018 We study the entropy evolution of black holes in Lovelock gravity by formulating a thermodynamic generalization of null Raychaudhuri equation. We show that the similarity between the expressions of entropy change of the black hole horizon due to perturbation and that of a fluid, which is out of equilibrium, transcends beyond general relativity to the Lovelock class of theories. Exploiting this analogy we find that the shear and bulk viscosities for the black holes in Lovelock theories exactly match with those obtained in the membrane paradigm and also from holographic considerations.
