Towards a waveextraction method for numerical relativity. V. Estimating the gravitationalwave content of spatial hypersurfaces
Abstract
We extract the Weyl scalars in the quasiKinnersley tetrad by finding initially the (gauge, tetrad, and backgroundindependent) transverse quasiKinnersley frame. This step still leaves two undetermined degrees of freedom: the ratio {psi}{sub 0}/{psi}{sub 4}, and one of the phases (the product {psi}{sub 0}{center_dot}{psi}{sub 4} and the sum of the phases are determined by the socalled BeetleBurko radiation scalar). The residual symmetry ('spin/boost') can be removed by gauge fixing of spin coefficients in two steps: First, we break the boost symmetry by requiring that {rho} corresponds to a global constant mass parameter that equals the ADM mass (or, equivalently in perturbation theory, that {rho} or {mu} equal their values in the noradiation limits), thus determining the two moduli of the Weyl scalars {psi}{sub 0}, {psi}{sub 4}, while leaving their phases as yet undetermined. Second, we break the spin symmetry by requiring that the ratio {pi}/{tau} gives the expected polarization state for the gravitational waves, thus determining the phases. Our method of gauge fixingspecifically its second stepis appropriate for cases for which the Weyl curvature is purely electric. Applying this method to Misner and BrillLindquist data, we explicitly find the Weyl scalars {psi}{sub 0} and {psi}{sub 4} in the quasiKinnersley tetrad.
 Authors:
 Department of Physics, University of Alabama in Huntsville, Huntsville, Alabama 35899 (United States)
 Publication Date:
 OSTI Identifier:
 21020408
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.084039; (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; COSMOLOGY; DEGREES OF FREEDOM; GRAVITATIONAL WAVES; MASS; PERTURBATION THEORY; POLARIZATION; SCALARS; SPIN; SYMMETRY; WEYL UNIFIED THEORY
Citation Formats
Burko, Lior M. Towards a waveextraction method for numerical relativity. V. Estimating the gravitationalwave content of spatial hypersurfaces. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.084039.
Burko, Lior M. Towards a waveextraction method for numerical relativity. V. Estimating the gravitationalwave content of spatial hypersurfaces. United States. doi:10.1103/PHYSREVD.75.084039.
Burko, Lior M. Sun .
"Towards a waveextraction method for numerical relativity. V. Estimating the gravitationalwave content of spatial hypersurfaces". United States.
doi:10.1103/PHYSREVD.75.084039.
@article{osti_21020408,
title = {Towards a waveextraction method for numerical relativity. V. Estimating the gravitationalwave content of spatial hypersurfaces},
author = {Burko, Lior M.},
abstractNote = {We extract the Weyl scalars in the quasiKinnersley tetrad by finding initially the (gauge, tetrad, and backgroundindependent) transverse quasiKinnersley frame. This step still leaves two undetermined degrees of freedom: the ratio {psi}{sub 0}/{psi}{sub 4}, and one of the phases (the product {psi}{sub 0}{center_dot}{psi}{sub 4} and the sum of the phases are determined by the socalled BeetleBurko radiation scalar). The residual symmetry ('spin/boost') can be removed by gauge fixing of spin coefficients in two steps: First, we break the boost symmetry by requiring that {rho} corresponds to a global constant mass parameter that equals the ADM mass (or, equivalently in perturbation theory, that {rho} or {mu} equal their values in the noradiation limits), thus determining the two moduli of the Weyl scalars {psi}{sub 0}, {psi}{sub 4}, while leaving their phases as yet undetermined. Second, we break the spin symmetry by requiring that the ratio {pi}/{tau} gives the expected polarization state for the gravitational waves, thus determining the phases. Our method of gauge fixingspecifically its second stepis appropriate for cases for which the Weyl curvature is purely electric. Applying this method to Misner and BrillLindquist data, we explicitly find the Weyl scalars {psi}{sub 0} and {psi}{sub 4} in the quasiKinnersley tetrad.},
doi = {10.1103/PHYSREVD.75.084039},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}

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