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Title: Slowly balding black holes

Abstract

The 'no-hair' theorem, a key result in general relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the no-hair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively ''frozen in'' the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes N{sub B}=e{Phi}{sub {infinity}}/({pi}c({h_bar}/2{pi})), where {Phi}{sub {infinity}}{approx_equal}2{pi}{sup 2}B{sub NS}R{sub NS}{sup 3}/(P{sub NS}c) is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. We test this theoretical result via 3-dimensional general relativistic plasma simulations of rotating black holes that start with a neutron star dipole magnetic field with no currents initially present outside the event horizon. The black hole's magnetosphere subsequently relaxesmore » to the split-monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum no-hair theorem.« less

Authors:
;  [1];  [2]
  1. Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, Indiana 47907-2036 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
21607903
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 84; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.84.084019; (c) 2011 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANGULAR MOMENTUM; ASYMPTOTIC SOLUTIONS; BLACK HOLES; DIPOLES; ELECTRIC CHARGES; GENERAL RELATIVITY THEORY; MAGNETIC FIELDS; MAGNETIC FLUX; MASS; NEUTRON STARS; RELATIVISTIC PLASMA; SIMULATION; THREE-DIMENSIONAL CALCULATIONS; TOPOLOGY; FIELD THEORIES; MATHEMATICAL SOLUTIONS; MATHEMATICS; MULTIPOLES; PLASMA; RELATIVITY THEORY; STARS

Citation Formats

Lyutikov, Maxim, McKinney, Jonathan C., and Department of Physics, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025. Slowly balding black holes. United States: N. p., 2011. Web. doi:10.1103/PHYSREVD.84.084019.
Lyutikov, Maxim, McKinney, Jonathan C., & Department of Physics, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025. Slowly balding black holes. United States. doi:10.1103/PHYSREVD.84.084019.
Lyutikov, Maxim, McKinney, Jonathan C., and Department of Physics, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025. 2011. "Slowly balding black holes". United States. doi:10.1103/PHYSREVD.84.084019.
@article{osti_21607903,
title = {Slowly balding black holes},
author = {Lyutikov, Maxim and McKinney, Jonathan C. and Department of Physics, Stanford University, 2575 Sand Hill Road, Menlo Park, California 94025},
abstractNote = {The 'no-hair' theorem, a key result in general relativity, states that an isolated black hole is defined by only three parameters: mass, angular momentum, and electric charge; this asymptotic state is reached on a light-crossing time scale. We find that the no-hair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can self-produce particles via vacuum breakdown forming a highly conducting plasma magnetosphere such that magnetic field lines are effectively ''frozen in'' the star both before and during collapse. In the limit of no resistivity, this introduces a topological constraint which prohibits the magnetic field from sliding off the newly-formed event horizon. As a result, during collapse of a neutron star into a black hole, the latter conserves the number of magnetic flux tubes N{sub B}=e{Phi}{sub {infinity}}/({pi}c({h_bar}/2{pi})), where {Phi}{sub {infinity}}{approx_equal}2{pi}{sup 2}B{sub NS}R{sub NS}{sup 3}/(P{sub NS}c) is the initial magnetic flux through the hemispheres of the progenitor and out to infinity. We test this theoretical result via 3-dimensional general relativistic plasma simulations of rotating black holes that start with a neutron star dipole magnetic field with no currents initially present outside the event horizon. The black hole's magnetosphere subsequently relaxes to the split-monopole magnetic field geometry with self-generated currents outside the event horizon. The dissipation of the resulting equatorial current sheet leads to a slow loss of the anchored flux tubes, a process that balds the black hole on long resistive time scales rather than the short light-crossing time scales expected from the vacuum no-hair theorem.},
doi = {10.1103/PHYSREVD.84.084019},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 84,
place = {United States},
year = 2011,
month =
}
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