Abstract
Let H be a finite involutary Hopfalgebra over the ring of integers Z. H is a separable Z-algebra iff H is dual to a finite groupring over Z. As a corollary one obtains a direct proof of a result by Tate-Oort: If H is of prime order p, then H is isomorphic to ZD or to its dual, where D=Z/pZ.
More generally some information is given about finite involutary Hopfalgebras over rings of algebraic integers.
Similar content being viewed by others
Literatur
DE MEYER, F. u. INGRAHAM, E.: Separable algebras over commutative rings. Lecture notes in mathematics 181. Berlin-Heidelberg-New York: Springer 1971.
HASSE, H.: Zahlentheorie. 2. Aufl. Berlin: Akademie-Verlag 1963.
LARSON, R.: Orders in Hopf algebras. Erscheint demnächst
LARSON, R. u. SWEEDLER, M.: An associative orthogonal bilinear form for Hopf algebras. Amer. J. Math. 91, 75–94 (1969).
OBERST, U. u. SCHNEIDER, H.-J.: Über Untergruppen von endlichen algebraischen Gruppen. Erscheint demnächst.
TATE, J. u. OORT, F.: Group schemes of prime order. Ann. scient. Ec. Norm. Sup. 3, 1–31 (1970).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Schneider, HJ. Bemerkung zu einer Arbeit von Tate-Oort. Manuscripta Math 8, 319–322 (1973). https://doi.org/10.1007/BF01297665
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF01297665