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arXiv · hep-th/9407003

Convex Bases of PBW type for Quantum Affine Algebras

Jonathan Beck
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Abstract

This note has two purposes. First we establish that the map defined in [L, $§40.2.5$ (a)] is an isomorphism for certain admissible sequences. Second we show the map gives rise to a convex basis of Poincaré--Birkhoff--Witt (PBW) type for $\bup$, an affine untwisted quantized enveloping algebra of Drinfel$'$d and Jimbo. The computations in this paper are made possible by extending the usual braid group action by certain outer automorphisms of the algebra.

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Jonathan Beck. 1994-07-01. Convex Bases of PBW type for Quantum Affine Algebras. https://doi.org/10.1007/bf02099742

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