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arXiv · hep-th/9504004

Multi-Instanton Effect in Two Dimensional QCD

Tetsuyuki Ochiai
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Abstract

We analyze multi-instanton sector in two dimensional U(N) Yang-Mills theory on a sphere. We obtain a contour intregrals representation of the multi-instanton amplitude and find ``neutral'' configurations of the even number instantons are dominant in the large N limit. Using this representation, we calculate 1,2,3,4 bodies interactions and the free energies for $N =3,4,5$ numerically and find that in fact the multi-instanton interaction effect essentially contribute to the large N phase transition discovered by Douglas and Kazakov.

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Tetsuyuki Ochiai. 1995-04-17. Multi-Instanton Effect in Two Dimensional QCD. https://doi.org/10.1142/s0217732395001678

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