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Solutions to the Quantized Knizhnik-Zamolodchikov Equation and the Bethe Ansatz

V. Tarasov·A. Varchenko
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Abstract

We give an integral representation for solutions to the quantized Knizhnik- Zamolodchikov equation (qKZ) associated with the Lie algebra $gl_{N+1}$. Asymptotic solutions to qKZ are constructed. The leading term of an asymptotic solution is the Bethe vector -- an eigenvector of the transfer-matrix of a quantum spin chain model. We show that the norm of the Bethe vector is equal to the product of the Hessian of a suitable function and an explicitly written rational function. This formula is a generalization of the Gaudin-Korepin formula for a norm of the Bethe vector. We show that, generically, the Bethe vectors form a base for the $gl_2$ case.

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V. Tarasov, A. Varchenko. 1994-11-24. Solutions to the Quantized Knizhnik-Zamolodchikov Equation and the Bethe Ansatz. https://arxiv.org/abs/hep-th/9411181

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