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Global structure of Witten's 2+1 gravity on ${\bf R}\times T^2$

Jorma Louko·Donald Marolf
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Abstract

We investigate the space ${\cal M}$ of classical solutions to Witten's formulation of 2+1 gravity on the manifold ${\bf R} \times T^2$. ${\cal M}$ is connected, but neither Hausdorff nor a manifold. However, removing from ${\cal M}$ a set of measure zero yields a connected manifold which is naturally viewed as the cotangent bundle over a non-Hausdorff base space. Avenues towards quantizing the theory are discussed in view of the relation between spacetime metrics and the various parts of~${\cal M}$. (Contribution to the proceedings of the Lanczos Centenary Conference, Raleigh, NC, December 12--17, 1993.)

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Jorma Louko, Donald Marolf. 1994-03-21. Global structure of Witten's 2+1 gravity on ${\bf R}\times T^2$. https://arxiv.org/abs/gr-qc/9403041

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