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Einstein's equations in Ashtekar's variables constitute a symmetric hyperbolic system

Mirta S. Iriondo·Enzo O. Leguizamón·Oscar A. Reula
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Abstract

We show that the 3+1 vacuum Einstein field equations in Ashtekar's variables constitutes a first order symmetric hyperbolic system for arbitrary but fixed lapse and shift fields, by suitable adding to the system terms proportional to the constraint equations.

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Mirta S. Iriondo, Enzo O. Leguizamón, Oscar A. Reula. 1997-10-01. Einstein's equations in Ashtekar's variables constitute a symmetric hyperbolic system. https://doi.org/10.1103/physrevlett.79.4732

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