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Quantum Gravity in 2+1 Dimensions: The Case of a Closed Universe

S. Carlip
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Abstract

In three spacetime dimensions, general relativity drastically simplifies, becoming a ``topological'' theory with no propagating local degrees of freedom. Nevertheless, many of the difficult conceptual problems of quantizing gravity are still present. In this review, I summarize the rather large body of work that has gone towards quantizing (2+1)-dimensional vacuum gravity in the setting of a spatially closed universe.

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S. Carlip. 2004-09-22. Quantum Gravity in 2+1 Dimensions: The Case of a Closed Universe. https://doi.org/10.12942/lrr-2005-1

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