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arXiv · hep-th/9204083

Two Dimensional Gauge Theories Revisited

Edward Witten
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Abstract

Topological gravity is equivalent to physical gravity in two dimensions in a way that is still mysterious, though by now it has been proved by Kontsevich. In this paper it is shown that a similar relation between topological and physical Yang-Mills theory holds in two dimensions; in this case, however, the relation can be explained by a direct mapping between the two path integrals. This (1) explains many strange facts about two dimensional Yang-Mills theory, like the way the partition function can be expressed exactly as a sum over classical solutions, including unstable ones; (2) makes the corresponding topological theory completely computable.

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Edward Witten. 1992-04-24. Two Dimensional Gauge Theories Revisited. https://doi.org/10.1016/0393-0440(92)90034-x

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