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Weight functions and Drinfeld currents

Benjamin Enriquez·Sergey Khoroshkin·Stanislav Pakuliak
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Abstract

A universal weight function for a quantum affine algebra is a family of functions with values in a quotient of its Borel subalgebra, satisfying certain coalgebraic properties. In representations of the quantum affine algebra it gives off-shell Bethe vectors and is used in the construction of solutions of the qKZ equations. We construct a universal weight function for each untwisted quantum affine algebra, using projections onto the intersection of Borel subalgebras of different types, and study its functional properties.

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Benjamin Enriquez, Sergey Khoroshkin, Stanislav Pakuliak. 2006-10-18. Weight functions and Drinfeld currents. https://arxiv.org/abs/math/0610398

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