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Time in (2+1)-Dimensional Quantum Gravity

S. Carlip
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Abstract

General relativity in three spacetime dimensions is used to explore three approaches to the ``problem of time'' in quantum gravity: the internal Schrödinger approach with mean extrinsic curvature as a time variable, the Wheeler-DeWitt equation, and covariant canonical quantization with ``evolving constants of motion.'' (To appear in {\em Proc.\ of the Lanczos Centenary Conference}, Raleigh, NC, December 1993.)

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S. Carlip. 1994-05-20. Time in (2+1)-Dimensional Quantum Gravity. https://arxiv.org/abs/gr-qc/9405043

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