All rational semisimple braided tensor categories are representation categories of weak quasi Hopf algebras. To prove this result we construct for any given category of this kind a weak quasi tensor functor to the category of finite dimensional vector spaces. This allows us to reconstruct a weak qua
On the Structure of Weak Hopf Algebras
✍ Scribed by Dmitri Nikshych
- Publisher
- Elsevier Science
- Year
- 2002
- Tongue
- English
- Weight
- 252 KB
- Volume
- 170
- Category
- Article
- ISSN
- 0001-8708
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✦ Synopsis
We study the group of group-like elements of a weak Hopf algebra and derive an analogue of Radford's formula for the fourth power of the antipode S; which implies that the antipode has a finite order modulo, a trivial automorphism. We find a sufficient condition in terms of TrðS 2 Þ for a weak Hopf algebra to be semisimple, discuss relation between semisimplicity and cosemisimplicity, and apply our results to show that a dynamical twisting deformation of a semisimple Hopf algebra is cosemisimple.
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