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arXiv · 1512.07629

Little Strings, Quasi-topological Sigma Model on Loop Group, and Toroidal Lie Algebras

Meer Ashwinkumar·Jingnan Cao·Yuan Luo·Meng-Chwan Tan·Qin Zhao
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Abstract

We study the ground states and left-excited states of the A_{k-1} N=(2,0) little string theory. Via a theorem by Atiyah [1], these sectors can be captured by a supersymmetric nonlinear sigma model on CP^1 with target space the based loop group of SU(k). The ground states, described by L^2-cohomology classes, form modules over an affine Lie algebra, while the left-excited states, described by chiral differential operators, form modules over a toroidal Lie algebra. We also apply our results to analyze the 1/2 and 1/4 BPS sectors of the M5-brane worldvolume theory.

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Meer Ashwinkumar, Jingnan Cao, Yuan Luo, Meng-Chwan Tan, Qin Zhao. 2018-01-25. Little Strings, Quasi-topological Sigma Model on Loop Group, and Toroidal Lie Algebras. https://doi.org/10.1016/j.nuclphysb.2018.01.014

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