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The Ground Ring of N=2 Minimal String Theory

Anatoly Konechny·Andrei Parnachev·David A. Sahakyan
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Abstract

We study the $\NN=2$ string theory or the $\NN=4$ topological string on the deformed CHS background. That is, we consider the $\NN=2$ minimal model coupled to the $\NN=2$ Liouville theory. This model describes holographically the topological sector of Little String Theory. We use degenerate vectors of the respective $\NN=2$ Verma modules to find the set of BRST cohomologies at ghost number zero--the ground ring, and exhibit its structure. Physical operators at ghost number one constitute a module of the ground ring, so the latter can be used to constrain the S-matrix of the theory. We also comment on the inequivalence of BRST cohomologies of the $\NN=2$ string theory in different pictures.

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Anatoly Konechny, Andrei Parnachev, David A. Sahakyan. 2005-09-21. The Ground Ring of N=2 Minimal String Theory. https://doi.org/10.1016/j.nuclphysb.2005.08.026

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