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arXiv · 1004.1222

On the instantons and the hypermultiplet mass of N=2* super Yang-Mills on S^4

Takuya Okuda·Vasily Pestun
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Abstract

We show that the physical N=4 super Yang-Mills theory on a four-sphere with an arbitrary gauge group receives no instanton contributions, by clarifying the relation between the hypermultiplet mass and the equivariant parameters of the mass-deformed theory preserving N=2 supersymmetry. The correct relation also implies that N=4 superconformal Yang-Mills theory with gauge group SU(2) corresponds to Liouville theory on a torus with the insertion of a non-trivial operator, rather than the identity as have been claimed in the literature.

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Takuya Okuda, Vasily Pestun. 2010-04-08. On the instantons and the hypermultiplet mass of N=2* super Yang-Mills on S^4. https://doi.org/10.1007/jhep03(2012)017

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