## The Brauer group of Yetter-Drinfel’d module algebras

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- by S. Caenepeel, F. Van Oystaeyen and Y. H. Zhang PDF
- Trans. Amer. Math. Soc.
**349**(1997), 3737-3771 Request permission

## Abstract:

Let $H$ be a Hopf algebra with bijective antipode. In a previous paper, we introduced $H$-Azumaya Yetter-Drinfel′d module algebras, and the Brauer group ${\mathrm {BQ}}(k,H)$ classifying them. We continue our study of ${\mathrm {BQ}}(k,H)$, and we generalize some properties that were previously known for the Brauer-Long group. We also investigate separability properties for $H$-Azumaya algebras, and this leads to the notion of strongly separable $H$-Azumaya algebra, and to a new subgroup of the Brauer group ${\mathrm {BQ}}(k,H)$.## References

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## Additional Information

**S. Caenepeel**- Affiliation: Faculty of Applied Sciences, Free University of Brussels, VUB, Pleinlaan 2, B-1050 Brussels, Belgium
- Email: scaenepe@vnet3.vub.ac.be
**F. Van Oystaeyen**- Affiliation: Department of Mathematics, University of Antwerp, UIA, Universiteitsplein 1, B-2610 Wilrijk, Belgium
- MR Author ID: 176900
- Email: francin@wins.uia.ac.be
**Y. H. Zhang**- Email: zhang@wins.uia.ac.be
- Received by editor(s): August 24, 1994
- Received by editor(s) in revised form: March 19, 1996
- Additional Notes: The third author wishes to thank the Free University of Brussels for its financial support during the time when this paper was written.
- © Copyright 1997 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**349**(1997), 3737-3771 - MSC (1991): Primary 16A16, 16A24
- DOI: https://doi.org/10.1090/S0002-9947-97-01839-4
- MathSciNet review: 1454120