Initialboundaryvalue problem of the selfgravitating scalar field in the BondiSachs gauge
Abstract
It is shown that, in the BondiSachs gauge that fixes the speed of incoming light rays to the value 1, the Einstein equations coupled to a scalar field in spherical symmetry are cast into a symmetrichyperbolic system of equations for the scalar field, lapse and shift as fundamental variables. In this system of equations, the lapse and shift are incoming characteristic fields, and the scalar field has three components: incoming, outgoing and static. A constraintpreserving boundary condition is prescribed by imposing the projection of the Einstein equation normal to the boundary at the outer value of the radial coordinate. The boundary condition specifies one of the two incoming metric fields. The remaining incoming metric field and the incoming scalar field component need to be specified arbitrarily. Numerical simulations of the scattering of the scalar field by a black hole in the nonlinear regime are presented that illustrate interesting facts about blackhole physics and the behavior of the characteristic variables of the problem.
 Authors:
 Department of Physics, Duquesne University, Pittsburgh, Pennsylvania 15282 (United States)
 (United States)
 Publication Date:
 OSTI Identifier:
 21011086
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevD.75.044021; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BLACK HOLES; BOUNDARY CONDITIONS; BOUNDARYVALUE PROBLEMS; COSMOLOGY; EINSTEIN FIELD EQUATIONS; NONLINEAR PROBLEMS; SCALAR FIELDS; SCATTERING; SYMMETRY
Citation Formats
Frittelli, Simonetta, Gomez, Roberto, and Pittsburgh Supercomputing Center, 300 S. Craig Ave, Pittsburgh, Pennsylvania 15213. Initialboundaryvalue problem of the selfgravitating scalar field in the BondiSachs gauge. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.044021.
Frittelli, Simonetta, Gomez, Roberto, & Pittsburgh Supercomputing Center, 300 S. Craig Ave, Pittsburgh, Pennsylvania 15213. Initialboundaryvalue problem of the selfgravitating scalar field in the BondiSachs gauge. United States. doi:10.1103/PHYSREVD.75.044021.
Frittelli, Simonetta, Gomez, Roberto, and Pittsburgh Supercomputing Center, 300 S. Craig Ave, Pittsburgh, Pennsylvania 15213. Thu .
"Initialboundaryvalue problem of the selfgravitating scalar field in the BondiSachs gauge". United States.
doi:10.1103/PHYSREVD.75.044021.
@article{osti_21011086,
title = {Initialboundaryvalue problem of the selfgravitating scalar field in the BondiSachs gauge},
author = {Frittelli, Simonetta and Gomez, Roberto and Pittsburgh Supercomputing Center, 300 S. Craig Ave, Pittsburgh, Pennsylvania 15213},
abstractNote = {It is shown that, in the BondiSachs gauge that fixes the speed of incoming light rays to the value 1, the Einstein equations coupled to a scalar field in spherical symmetry are cast into a symmetrichyperbolic system of equations for the scalar field, lapse and shift as fundamental variables. In this system of equations, the lapse and shift are incoming characteristic fields, and the scalar field has three components: incoming, outgoing and static. A constraintpreserving boundary condition is prescribed by imposing the projection of the Einstein equation normal to the boundary at the outer value of the radial coordinate. The boundary condition specifies one of the two incoming metric fields. The remaining incoming metric field and the incoming scalar field component need to be specified arbitrarily. Numerical simulations of the scattering of the scalar field by a black hole in the nonlinear regime are presented that illustrate interesting facts about blackhole physics and the behavior of the characteristic variables of the problem.},
doi = {10.1103/PHYSREVD.75.044021},
journal = {Physical Review. D, Particles Fields},
number = 4,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

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