Einstein’s equations in the presence of signature change
نویسنده
چکیده
We discuss Einstein’s field equations in the presence of signature change using variational methods, obtaining a generalization of the Lanczos equation relating the distributional term in the stress tensor to the discontinuity of the extrinsic curvature. In particular, there is no distributional term in the stress tensor, and hence no surface layer, precisely when the extrinsic curvature is continuous, in agreement with the standard result for constant signature. © 1996 American Institute of Physics. @S0022-2488~96!02611-4#
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