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A symmetry-breaking mechanism for the Z4 general-covariant evolution system

C. Bona·T. Ledvinka·C. Palenzuela·M. Zacek
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Abstract

The general-covariant Z4 formalism is further analyzed. The gauge conditions are generalized with a view to Numerical Relativity applications and the conditions for obtaining strongly hyperbolic evolution systems are given both at the first and the second order levels. A symmetry-breaking mechanism is proposed that allows one, when applied in a partial way, to recover previously proposed strongly hyperbolic formalisms, like the BSSN and the Bona-Massó ones. When applied in its full form, the symmetry breaking mechanism allows one to recover the full five-parameter family of first order KST systems. Numerical codes based in the proposed formalisms are tested. A robust stability test is provided by evolving random noise data around Minkowski space-time. A strong field test is provided by the collapse of a periodic background of plane gravitational waves, as described by the Gowdy metric.

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C. Bona, T. Ledvinka, C. Palenzuela, M. Zacek. 2004-03-22. A symmetry-breaking mechanism for the Z4 general-covariant evolution system. https://doi.org/10.1103/physrevd.69.064036

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