Narrow Results

We study the thermodynamics and spectroscopy of a (2+1)-dimensional black hole proposed by Mandal et al.¹ [Mod. Phys. Lett. A6, 1685 (1991)]. We put the background spacetime in Kruskal like co-ordinate and find period with respect to Euclidean time. Different thermodynamic quantities like entropy, specific heat, temperature etc. are obtained. The adiabatic invariant for the black hole is found and quantized using Bohr–Sommerfeld quantization rule. The study shows that the area spectrum of MSW black hole is equally spaced and the value of spacing is found to be ℏ.

In this paper, we study the Dirac quasinormal modes of an uncharged 2+1 black hole proposed by Mandal et al. and referred to as MSW black hole. The quasinormal mode is studied using WKB approximation method. The study shows that the imaginary part of quasinormal frequencies increases indicating that the oscillations are damping and hence the black hole is stable against Dirac perturbations.

In this paper, the linear stability of static Mandal–Sengupta–Wadia (MSW) black holes in (2 + 1)-dimensional gravity against circularly symmetric perturbations is studied. Our analysis only applies to non-extremal configurations, thus leaving out the case of the extremal (2 + 1) MSW solution. The associated fields are assumed to have small perturbations in these static backgrounds. We then consider the dilaton equation and specific components of the linearized Einstein equations. The resulting effective Klein–Gordon equation is reduced to the Schrödinger-like wave equation with the associated effective potential. Finally, it is shown that MSW black holes are stable against the small time-dependent perturbations.