Discrete quantum spectrum of black holes

Abstract

The quantum genesis of Hawking radiation is a long-standing puzzle in black hole physics. Semi-classically one can argue that the spectrum of radiation emitted by a black hole look very much sparse unlike what is expected from a thermal object. It was demonstrated through a simple quantum model that a quantum black hole will retain a discrete profile, at least in the weak energy regime. However, it was suggested that this discreteness might be an artifact of the simplicity of eigen-spectrum of the model considered. Different quantum theories can, in principle, give rise to different complicated spectra and make the radiation from black hole dense enough in transition lines, to make them look continuous in profile. We show that such a hope from a geometry-quantized black hole is not realized as long as large enough black holes are dubbed with a classical mass area relation in any gravity theory ranging from GR, Lanczos-Lovelock to f(R) gravity. We show that the smallest frequency of emission from black hole in any quantum description, is bounded from below, to be of the order of its inverse mass. That leaves the emission with only two possibilities. It can either be non-thermal, or it can be thermal only with the temperature being much larger than 1/M.

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References in corpus (20)

• Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models
• f(R,T) gravity
• Thermodynamic route to Field equations in Lanczos-Lovelock Gravity
• Solar system constraints on f(T) gravity
• Static Solutions with Spherical Symmetry in f(T) Theories
• The Hawking cascade from a black hole is extremely sparse
• Emergent Gravity Paradigm: Recent Progress
• Thermodynamical interpretation of the geometrical variables associated with null surfaces
• Noether current from the surface term of gravitational action, Virasoro algebra and horizon entropy
• Komar Integrals in Higher (and Lower) Derivative Gravity
• Evolution of Spacetime arises due to the departure from Holographic Equipartition in all Lanczos-Lovelock Theories of Gravity
• A discerning gravitational property for gravitational equation in higher dimensions
• Mass Spectrum and Statistical Entropy of the BTZ black hole from Canonical Quantum Gravity
• Geometrical variables with direct thermodynamic significance in Lanczos-Lovelock gravity
• A quantum peek inside the black hole event horizon
• Structure of Lanczos-Lovelock Lagrangians in Critical Dimensions
• Black hole kinematics: the "in"-vacuum energy density and flux for different observers
• Extracting information about the initial state from the black hole radiation
• Spectrum and Statistical Entropy of AdS Black Holes
• Free fall onto evaporating black holes at the quantum limit

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• Dynamical Love for area quantized black holes
• Hidden Messenger from Quantum Geometry: Towards Information Conservation in Quantum Gravity
• New Kind of Echo from Quantum Black Holes
• Decoding infrared imprints of quantum origins of black holes
• Quantum leaps of black holes: Magnifying glasses of quantum gravity