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Twisted Hopf Algebras, Ringel–Hall Algebras, and Green's Categories: With an appendix by the referee

✍ Scribed by Libin Li; Pu Zhang


Publisher
Elsevier Science
Year
2000
Tongue
English
Weight
215 KB
Volume
231
Category
Article
ISSN
0021-8693

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✦ Synopsis


The concept and some basic properties of a twisted Hopf algebra are introduced and investigated. Its unique difference from a Hopf algebra is that the comultiplication ␦ : A ª A m A is an algebra homomorphism, not for the componentwise multiplication on A m A, but for the twisted multiplication on A m A given by Lusztig's rule.

Also, it is proved that any object A in Green's category has a twisted Hopf algebra structure, any morphism between objects is a twisted Hopf algebra homo-Ž . morphism, the antipode s of A is self-adjoint under the Lusztig form y, y on A, Ž . and the Green polynomials M t share a so-called cyclic-symmetry.

a, b