Slowly balding black holes
The 'nohair' 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 lightcrossing time scale. We find that the nohair theorem is not formally applicable for black holes formed from the collapse of a rotating neutron star. Rotating neutron stars can selfproduce 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 newlyformed 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 3dimensional 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 »
 Authors:

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 Department of Physics, Purdue University, 525 Northwestern Avenue, West Lafayette, Indiana 479072036 (United States)
 (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; THREEDIMENSIONAL CALCULATIONS; TOPOLOGY FIELD THEORIES; MATHEMATICAL SOLUTIONS; MATHEMATICS; MULTIPOLES; PLASMA; RELATIVITY THEORY; STARS