Thermal dimensional reduction and black hole evaporation

Abstract An important open question in black hole thermodynamics is about the existence of a “mass gap” between an extremal black hole and the lightest near-extremal state within a sector of fixed charge. In this paper, we reliably compute the partition function of Reissner-Nordström near-extremal black holes at temperature scales comparable to the conjectured gap. We find that the density of states at fixed charge does not exhibit a gap; rather, at the expected gap energy scale, we see a continuum of states. We compute the partition function in the canonical and grand canonical ensembles, keeping track of all the fields appearing through a dimensional reduction on S2 in the near-horizon region. Our calculation shows that the relevant degrees of freedom at low temperatures are those of 2d Jackiw-Teitelboim gravity coupled to the electromagnetic U(1) gauge field and to an SO(3) gauge field generated by the dimensional reduction.

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Linear mass Vaidya metric at the end of black hole evaporation

Physical Review D ◽

10.1103/physrevd.91.044020 ◽

2015 ◽

Vol 91 (4) ◽

Cited By ~ 3

Author(s):

Martin O’Loughlin

Keyword(s):

Black Hole ◽

Linear Mass ◽

Black Hole Evaporation ◽

Vaidya Metric

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THE UNREASONABLE EFFECTIVENESS OF EXPONENTIALLY SUPPRESSED CORRECTIONS IN PRESERVING INFORMATION

International Journal of Modern Physics D ◽

10.1142/s0218271813420303 ◽

2013 ◽

Vol 22 (12) ◽

pp. 1342030 ◽

Cited By ~ 9

Author(s):

KYRIAKOS PAPADODIMAS ◽

SUVRAT RAJU

Keyword(s):

Hilbert Space ◽

Black Hole ◽

Quantum Mechanics ◽

Nonperturbative Effects ◽

Von Neumann Entropy ◽

Von Neumann ◽

Information Theoretic ◽

Black Hole Evaporation ◽

Strong Subadditivity ◽

Unreasonable Effectiveness

We point out that nonperturbative effects in quantum gravity are sufficient to reconcile the process of black hole evaporation with quantum mechanics. In ordinary processes, these corrections are unimportant because they are suppressed by e-S. However, they gain relevance in information-theoretic considerations because their small size is offset by the corresponding largeness of the Hilbert space. In particular, we show how such corrections can cause the von Neumann entropy of the emitted Hawking quanta to decrease after the Page time, without modifying the thermal nature of each emitted quantum. Second, we show that exponentially suppressed commutators between operators inside and outside the black hole are sufficient to resolve paradoxes associated with the strong subadditivity of entropy without any dramatic modifications of the geometry near the horizon.

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BLACK HOLE EVAPORATION BASED UPON A q-DEFORMATION DESCRIPTION

International Journal of Modern Physics A ◽

10.1142/s0217751x05024377 ◽

2005 ◽

Vol 20 (26) ◽

pp. 6039-6049 ◽

Cited By ~ 2

Author(s):

XIN ZHANG

Keyword(s):

Black Hole ◽

Degrees Of Freedom ◽

Radiation Spectrum ◽

Correlation Effect ◽

Space Time ◽

Noncommutative Space ◽

Schwarzschild Black Hole ◽

Black Hole Evaporation ◽

Starting Point ◽

New Distribution

A toy model based upon the q-deformation description for studying the radiation spectrum of black hole is proposed. The starting point is to make an attempt to consider the space–time noncommutativity in the vicinity of black hole horizon. We use a trick that all the space–time noncommutative effects are ascribed to the modification of the behavior of the radiation field of black hole and a kind of q-deformed degrees of freedom are postulated to mimic the radiation particles that live on the noncommutative space–time, meanwhile the background metric is preserved as usual. We calculate the radiation spectrum of Schwarzschild black hole in this framework. The new distribution deviates from the standard thermal spectrum evidently. The result indicates that some correlation effect will be introduced to the system if the noncommutativity is taken into account. In addition, an infrared cutoff of the spectrum is the prediction of the model.

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Remarks on Remnants by Fermions’ Tunnelling from Black Strings

Advances in High Energy Physics ◽

10.1155/2014/620157 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 22

Author(s):

Deyou Chen ◽

Zhonghua Li

Keyword(s):

Black Hole ◽

Quantum Gravity ◽

Uncertainty Principle ◽

Final Stage ◽

Generalized Uncertainty Principle ◽

Black Hole Evaporation ◽

Quantum Numbers ◽

Black Strings

Hawking’s calculation is unable to predict the final stage of the black hole evaporation. When effects of quantum gravity are taken into account, there is a minimal observable length. In this paper, we investigate fermions’ tunnelling from the charged and rotating black strings. With the influence of the generalized uncertainty principle, the Hawking temperatures are not only determined by the rings, but also affected by the quantum numbers of the emitted fermions. Quantum gravity corrections slow down the increases of the temperatures, which naturally leads to remnants left in the evaporation.

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