Abstract
We first prove that for a finite dimensional non-semisimple Hopf algebra H, the trivial H-module is not projective and so the almost split sequence ended with k exists. By this exact sequence, for all indecomposable H-module X, we can construct a special kind of exact sequence ending with it. The main aim of this paper is to determine when this special exact sequence is an almost split one. For this aim, we restrict H to be unimodular and the square of its antipode to be an inner automorphism. As a special case, we give an application to the quantum double D(H)=(H op)*⋈H) of any non-semisimple Hopf algebra.
Similar content being viewed by others
References
Auslander, M., Reiten, I., Smalø, S.O., 1995. Representation Theory of Artin Algebras. Cambridge University Press, Cambridge.
Böhm, G., Nill, F., Szlachanyi, K., 1999. Weak Hopf algebras I. Integral theory and C*-structure. J. Algebra, 221(2):385–438. [doi:10.1006/jabr.1999.7984]
Kassel, C., 1995. Quantum Groups. GTM 155. Springer-Verlag, p.127–128.
Lorenz, M., 1997. Representation of finite dimensional Hopf algebras. J. Algebra, 188(2):476–505. [doi:10.1006/jabr.1996.6827]
Montgomery, S., 1993. Hopf Algebras and Their Actions on Rings. CBMS, Lecture in Math, Providence, RI, 82:215–217.
Author information
Authors and Affiliations
Additional information
Project (No. 10371107) supported by the National Natural Science Foundation of China
Rights and permissions
About this article
Cite this article
Shi, Mh. Almost split sequences for symmetric non-semisimple Hopf algebras. J. Zhejiang Univ. - Sci. A 7, 1077–1083 (2006). https://doi.org/10.1631/jzus.2006.A1077
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1631/jzus.2006.A1077