Related papers: Horizon induces instability locally and creates qu…
We analyze spacetimes with horizons and study the thermodynamic aspects of causal horizons, suggesting that the resemblance between gravitational and thermodynamic systems has a deeper quantum mechanical origin. We find that the observer…
We work with the notion of apparent/trapping horizons for spherically symmetric, dynamical spacetimes: these are quasi-locally defined, simply based on the behaviour of congruence of light rays. We show that the sign of the dynamical…
We study Hawking radiation as a phenomenon of tunneling through event horizons of charged torus-like as well as dilaton black holes involving cosmological constant based on Kerner and Mann's formulation. We obtain tunneling probabilities as…
The horizon is a classical concept that arises in general relativity, and is therefore not clearly defined when the source cannot be reliably described by classical physics. To any (sufficiently) localised quantum mechanical wave-function,…
Spatially varying near-horizon fluctuations of temperature of a Schwarzschild Black Hole is considered within the Euclidean Gravity approach. We present evidence that suggests that such fluctuations in temperature are closely related with…
The semi-classical derivation of Hawking radiation for axially symmetric, stationary spacetimes with a Killing horizon is examined following the recent quasi-classical tunneling analysis and a simple formula is found for the inverse Hawking…
Because of colour confinement, the physical vacuum forms an event horizon for quarks and gluons; this can be crossed only by quantum tunneling, i.e., through the QCD counterpart of Hawking radiation by black holes. Since such radiation…
A criterion of thermal stability is derived for electrically charged quantum} black holes having large horizon area (compared to Planck area), as an inequality between the mass of the black hole and its microcanonical entropy. The…
The exponential blueshift associated with the event horizon of a black hole makes conformal symmetry play a fundamental role in accounting for its thermal properties. Using a derivation based on two-point functions, we show that the…
A black hole, surrounded by a reflecting shell, acts as an effective star-like object with respect to the outer region that leads to vacuum polarization outside, where the quantum fields are in the Boulware state. We find the quantum…
By reintroducing Lorentz invariance in canonical loop quantum gravity, we define a geometrical notion of temperature for quantum isolated horizons. This is done by demanding that the horizon state satisfying the boundary conditions be a…
To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such ``horizon constraints'' allow the use of conformal…
Tunneling processes through black hole horizons have recently been investigated in the framework of WKB theory discovering interesting interplay with the Hawking radiation. In this paper we instead adopt the point of view proper of QFT in…
Analyzing exact solutions of the Einstein-Maxwell equations in the Kerr-Schild formalism we show that black hole horizon is instable with respect to electromagnetic excitations. Contrary to perturbative smooth harmonic solutions, the exact…
The gravitational force harbours a fundamental instability against collapse. In standard General Relativity without Quantum Mechanics, this implies the existence of black holes as natural, stable solutions of Einstein's equations. If one…
Hawking radiation originates from a "quantum atmosphere" around black holes, not necessarily from the vicinity of the horizon. We examine and discuss the properties of quantum atmospheres of asymptotically flat Reissner-Nordstr\"om black…
We have developed a theoretical formalism to introduce temperature as a parameter into the framework of non-relativistic quantum mechanics using the laws of classical thermodynamics and the canonical ensemble scheme of statistical…
The instability against emission of fermionic particles by the trapping horizon of an evolving black hole is analyzed using the Hamilton-Jacobi tunneling method. This method automatically selects one special expression for the surface…
Synthetic horizons in models for quantum matter provide an alternative route to explore fundamental questions of modern gravitational theory. Here, we apply these concepts to the problem of emergence of thermal quantum states in the…
An effective black-hole-like horizon occurs, for electromagnetic waves in matter, at a surface of singular electric and magnetic permeabilities. In a physical dispersive medium this horizon disappears for wave numbers with $k>k_c$.…