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arXiv · hep-th/9301075

Berenstein-Zelevinsky triangles, elementary couplings and fusion rules

L. Begin·Anatol N. Kirillov·P. Mathieu·M. A. Walton
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Abstract

We present a general scheme for describing su(N)_k fusion rules in terms of elementary couplings, using Berenstein-Zelevinsky triangles. A fusion coupling is characterized by its corresponding tensor product coupling (i.e. its Berenstein-Zelevinsky triangle) and the threshold level at which it first appears. We show that a closed expression for this threshold level is encoded in the Berenstein-Zelevinsky triangle and an explicit method to calculate it is presented. In this way a complete solution of su(4)_k fusion rules is obtained.

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L. Begin, Anatol N. Kirillov, P. Mathieu, M. A. Walton. 1993-01-18. Berenstein-Zelevinsky triangles, elementary couplings and fusion rules. https://doi.org/10.1007/bf00761494

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