Abstract
We find a one-parameter family of variables which recast the Einstein equations into first-order symmetric hyperbolic form for any fixed choice of gauge. Hyperbolicity considerations lead us to a redefinition of the lapse in terms of an arbitrary factor times a power of the determinant of the 3-metric; under certain assumptions, the exponent can be chosen arbitrarily, but positive, with no implication of gauge fixing.
- Received 26 January 1996
DOI:https://doi.org/10.1103/PhysRevLett.76.4667
©1996 American Physical Society