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arXiv · gr-qc/9904075

Causal structure and degenerate phase boundaries

Yongge Ma·Canbin Liang
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Abstract

Timelike and null hypersurfaces in the degenerate space-times in the Ashtekar theory are defined in the light of the degenerate causal structure proposed by Matschull. Using the new definition of null hypersufaces, the conjecture that the "phase boundary" separating the degenerate space-time region from the non-degenerate one in Ashtekar's gravity is always null is proved under certain circumstances.

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Yongge Ma, Canbin Liang. 1999-04-29. Causal structure and degenerate phase boundaries. https://doi.org/10.1103/physrevd.59.044008

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