The variational method, backreactions, and the absorption probability in Wald type problems

Abstract

We argue that the variational method in Wald type thought experiments, involves order of magnitude problems when one imposes the fact that $\delta M$ is inherently a first order quantity itself. One observes that the contribution of the second order perturbations is actually of the fourth order. Therefore backreactions have to be explicitly calculated. Here, we re-consider the overspinning problem for Kerr-Newman black holes interacting with test fields. We calculate the backreaction effects due to the induced increase in the angular velocity of the event horizon, which brings a partial solution to the overspinning problem. To bring an ultimate solution, we argue that the absorption probability should be taken into account in Wald type problems where black holes interact with test fields. This fundamentally alters the course of the analysis of the thought experiments. Due to the fact that a small fraction of the challenging modes is absorbed by the black holes, overspinning is prevented for both nearly extremal and extremal cases. Some extreme cases are easily fixed by backreaction effects. The arguments do not apply to the generic overspinning by fermionic fields for which the absorption probability is positive definite.

Accepted to appear in European Physical Journal C

References in corpus (47)

• Overcharging a Black Hole and Cosmic Censorship
• Over-spinning a black hole with a test body
• Test bodies and naked singularities: is the self-force the cosmic censor?
• Gedanken Experiments to Destroy a Black Hole II: Kerr-Newman Black Holes Cannot be Over-Charged or Over-Spun
• Weak Cosmic Censorship: As Strong as Ever
• Destroying extremal Kerr-Newman black holes with test particles
• Destroying a near-extremal Kerr-Newman black hole
• Test fields cannot destroy extremal black holes
• Dyonic Kerr-Newman black holes, complex scalar field and Cosmic Censorship
• Overspinning a nearly extreme charged black hole via a quantum tunneling process
• Cosmic censorship in overcharging a Reissner-Nordström black hole via charged particle absorption
• Cosmic Censorship, Black Holes and Integer-spin Test Fields
• Destroying Kerr-Sen black holes
• Weak Cosmic Censorship Conjecture in Kerr-(Anti-)de Sitter Black Hole with Scalar Field
• Cosmic Censorship and Weak Gravity Conjecture in the Einstein-Maxwell-dilaton theory
• Overcharging higher-dimensional black holes with point particles
• Thermodynamics with Pressure and Volume under Charged Particle Absorption
• Cosmic Censorship of Rotating Anti-de Sitter Black Hole
• Thermodynamics and weak cosmic censorship conjecture in extended phase spaces of anti-de Sitter black holes with particles' absorption
• Challenging the weak cosmic censorship conjecture with charged quantum particles
• Overspinning a nearly extreme black hole and the Weak Cosmic Censorship conjecture
• Overspinning BTZ black holes with test particles and fields
• Can test fields destroy the event horizon in the Kerr-Taub-NUT spacetime?
• Can quantum mechanics fool the cosmic censor?
• Thermodynamics and weak cosmic censorship conjecture in the charged RN-AdS black hole surrounded by quintessence under the scalar field
• Weak Cosmic Censorship, Superradiance and Quantum Particle Creation
• Thermodynamics and weak cosmic censorship conjecture in Reissner-Nordstr$\ddot{o}$m anti-de Sitter black holes with scalar field
• Electromagnetic field and cosmic censorship
• Spacetime Singularities and Cosmic Censorship Conjecture: A Review with Some Thoughts
• Weak cosmic censorship, dyonic Kerr-Newman black holes and Dirac fields
• Return of the quantum cosmic censor
• Thermodynamics of Three-dimensional Black Holes via Charged Particle Absorption
• Stability of event horizons against neutrino flux: The classical picture
• Weak cosmic censorship conjecture in Einstein-Born-Infeld black holes
• Testing Cosmic Censorship Conjecture for Extremal and Near-extremal (2+1)-dimensional MTZ Black Holes
• Kerr-Newman black holes can be generically overspun
• Violations of the weak cosmic censorship conjecture in the higher dimensional $f(R)$ black holes with pressure
• Strong Cosmic Censorship under Quasinormal Modes of Non-Minimally Coupled Massive Scalar Field
• Over-spinning Kerr-Sen black holes with test fields
• Destroying extremal magnetized black holes
• String analog of Reissner-Nordström black holes cannot be overcharged
• Overspinning Kerr-MOG black holes by test fields and the third law of black hole dynamics
• Hawking radiation as the cosmic censor
• Overcharging problem and thermodynamics in extended phase spaces
• Charged Particle and Strong Cosmic Censorship in Reissner-Nordström-de Sitter Black Holes
• Is there a mode stability paradox for neutrino perturbations of Kerr black holes?
• Quasinormal Modes of Massive Scalar Field with Nonminimal Coupling in Higher-Dimensional de Sitter Black Hole with Single Rotation

Cited by in corpus (7)

• Cosmic censorship, massless fermionic test fields, and absorption probabilities
• Challenging event horizons with spin (3/2) fields
• Spin-2 fields and cosmic censorship
• Can the induced increase in the angular velocity prevent the overspinning of BTZ black holes?
• The First Law and Weak Cosmic Censorship for de Sitter Black Holes
• Second order variations and the overspinning problem in Kerr-Taub-NUT spacetime
• Self energy in Kerr-Sen space-time incorporated to overspinning and overcharging problems