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arXiv · 1403.6572

Multi-matrix models and Noncommutative Frobenius algebras obtained from symmetric groups and Brauer algebras

Yusuke Kimura
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Abstract

It has been understood that correlation functions of multi-trace operators in ${\cal N}=4$ SYM can be neatly computed using the group algebra of symmetric groups or walled Brauer algebras. On the other hand such algebras have been known to construct 2D topological field theories (TFTs). After reviewing the construction of 2D TFTs based on symmetric groups, we construct 2D TFTs based on walled Brauer algebras. In the construction, the introduction of a dual basis manifests a similarity between the two theories. We next construct a class of 2D field theories whose physical operators have the same symmetry as multi-trace operators constructed from some matrices. Such field theories correspond to non-commutative Frobenius algebras. A matrix structure arises as a consequence of the noncommutativity. Correlation functions of the Gaussian complex multi-matrix models can be translated into correlation functions of the two-dimensional field theories.

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Yusuke Kimura. 2014-05-12. Multi-matrix models and Noncommutative Frobenius algebras obtained from symmetric groups and Brauer algebras. https://doi.org/10.1007/s00220-014-2231-6

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