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A hyperbolic slicing condition adapted to Killing fields and densitized lapses

Miguel Alcubierre·Alejandro Corichi·Jose A. Gonzalez·Dario Nunez·Marcelo Salgado
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Abstract

We study the properties of a modified version of the Bona-Masso family of hyperbolic slicing conditions. This modified slicing condition has two very important features: In the first place, it guarantees that if a spacetime is static or stationary, and one starts the evolution in a coordinate system in which the metric coefficients are already time independent, then they will remain time independent during the subsequent evolution, {\em i.e.} the lapse will not evolve and will therefore not drive the time lines away from the Killing direction. Second, the modified condition is naturally adapted to the use of a densitized lapse as a fundamental variable, which in turn makes it a good candidate for a dynamic slicing condition that can be used in conjunction with some recently proposed hyperbolic reformulations of the Einstein evolution equations.

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Miguel Alcubierre, Alejandro Corichi, Jose A. Gonzalez, Dario Nunez, Marcelo Salgado. 2003-08-26. A hyperbolic slicing condition adapted to Killing fields and densitized lapses. https://doi.org/10.1088/0264-9381%2F20%2F18%2F308

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