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arXiv · hep-th/9612246

Topology Change and theta-Vacua in 2D Yang-Mills Theory

Tom D. Imbo·P. Teotonio-Sobrinho
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Abstract

We discuss the existence of $θ$-vacua in pure Yang-Mills theory in two space-time dimensions. More precisely, a procedure is given which allows one to classify the distinct quantum theories possessing the same classical limit for an arbitrary connected gauge group G and compact space-time manifold M (possibly with boundary) possessing a special basepoint. For any such G and M it is shown that the above quantizations are in one-to-one correspondence with the irreducible unitary representations (IUR's) of $π_1(G)$ if M is orientable, and with the IUR's of $π_1(G)/2π_1(G)$ if M is nonorientable.

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Tom D. Imbo, P. Teotonio-Sobrinho. 1996-12-29. Topology Change and theta-Vacua in 2D Yang-Mills Theory. https://doi.org/10.1016/s0550-3213(97)00378-7

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