Matter Accretion Versus Semiclassical Bounce in Schwarzschild Interior

We discuss the properties of the previously constructed model of a Schwarzschild black hole interior where the singularity is replaced by a regular bounce, ultimately leading to a white hole. We assume that the black hole is young enough so that the Hawking radiation may be neglected. The model is semiclassical in nature and uses as a source of gravity the effective stress-energy tensor (SET) corresponding to vacuum polarization of quantum fields, and the minimum spherical radius is a few orders of magnitude larger than the Planck length, so that the effects of quantum gravity should still be negligible. We estimate the other quantum contributions to the effective SET, caused by a nontrivial topology of spatial sections and particle production from vacuum due to a nonstationary gravitational field and show that these contributions are negligibly small as compared to the SET due to vacuum polarization. The same is shown for such classical phenomena as accretion of different kinds of matter to the black hole and its further motion to the would-be singularity. Thus, in a clear sense, our model of a semiclassical bounce instead of a Schwarzschild singularity is stable under both quantum and classical perturbations.

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A possible semiclassical bounce instead of a Schwarzschild singularity

International Journal of Modern Physics A ◽

10.1142/s0217751x20400515 ◽

2020 ◽

Vol 35 (02n03) ◽

pp. 2040051

Author(s):

K. A. Bronnikov ◽

S. V. Bolokhov ◽

M. V. Skvortsova

Keyword(s):

Black Hole ◽

Vacuum Polarization ◽

Particle Creation ◽

Energy Tensor ◽

Quantum Fields ◽

Stress Energy Tensor ◽

Planck Length ◽

Schwarzschild Black Hole ◽

Stress Energy

We have previously shown that the singularity in a Schwarzschild black hole of stellar or larger mass may be avoided in a semiclassical manner by using as a source of gravity the stress-energy tensor (SET) corresponding to vacuum polarization of quantum fields, with a minimum spherical radius a few orders of magnitude larger than the Planck length. In this note we estimate the nonlocal contribution to the total SET due to particle creation from vacuum. We show that this contribution is negligibly small as compared to vacuum polarization and does not affect the previously suggested scenario.

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Renormalized stress-energy tensor near the horizon of a slowly evolving, rotating black hole

Physical Review D ◽

10.1103/physrevd.39.2125 ◽

1989 ◽

Vol 39 (8) ◽

pp. 2125-2154 ◽

Cited By ~ 94

Author(s):

Valery P. Frolov ◽

Kip S. Thorne

Keyword(s):

Black Hole ◽

Energy Tensor ◽

Stress Energy Tensor ◽

Rotating Black Hole ◽

Stress Energy

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Stability of the Regular Hayward Thin-Shell Wormholes

Advances in High Energy Physics ◽

10.1155/2016/2868750 ◽

2016 ◽

Vol 2016 ◽

pp. 1-13 ◽

Cited By ~ 8

Author(s):

M. Sharif ◽

Saadia Mumtaz

Keyword(s):

Black Hole ◽

Thin Shell ◽

Energy Conditions ◽

Stability Conditions ◽

Energy Tensor ◽

Stress Energy Tensor ◽

Cosmic Expansion ◽

Stress Energy ◽

Thin Shell Wormholes ◽

The Stability

The aim of this paper is to construct regular Hayward thin-shell wormholes and analyze their stability. We adopt Israel formalism to calculate surface stresses of the shell and check the null and weak energy conditions for the constructed wormholes. It is found that the stress-energy tensor components violate the null and weak energy conditions leading to the presence of exotic matter at the throat. We analyze the attractive and repulsive characteristics of wormholes corresponding toar>0andar<0, respectively. We also explore stability conditions for the existence of traversable thin-shell wormholes with arbitrarily small amount of fluid describing cosmic expansion. We find that the space-time has nonphysical regions which give rise to event horizon for0<a0<2.8and the wormhole becomes nontraversable producing a black hole. The nonphysical region in the wormhole configuration decreases gradually and vanishes for the Hayward parameterl=0.9. It is concluded that the Hayward and Van der Waals quintessence parameters increase the stability of thin-shell wormholes.

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