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arXiv · hep-th/9704076

N=2 Worldsheet Instantons Yield Cubic Self-Dual Yang-Mills

Olaf Lechtenfeld·Warren Siegel
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Abstract

When the gauge instantons on the N=2 string worldsheet are properly included in the sum over topologies, the breaking of SO(2,2) Lorentz symmetry in R^{2,2} is parametrized by a spacetime twistor containing the string coupling and theta angle. The resulting (tree-level) effective action for the open string is not Yang's but Leznov's cubic action for self-dual Yang-Mills in a light-cone gauge. In the closed case, Plebanski's action for self-dual gravity gets modified analogously. In contrast to the N=1 NSR string, picture-changing is not locally invertible, but produces a semi-infinite tower of massless physical states with ever-increasing spin, perhaps related to harmonic superspace. A truncation yields the two-field action of Chalmers and Siegel.

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Olaf Lechtenfeld, Warren Siegel. 1997-04-09. N=2 Worldsheet Instantons Yield Cubic Self-Dual Yang-Mills. https://doi.org/10.1016/s0370-2693(97)00595-9

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