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On modular extensions

Author: Shizuka Sato
Journal: Proc. Amer. Math. Soc. 109 (1990), 621-626
MSC: Primary 13B02; Secondary 12F05, 13B10, 13G05
MathSciNet review: 1019282
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Abstract: M. E. Sweedler has proved that modular extensions of fields are characterized by a tensor product of primitive elements, and also by the equivalent condition that the ground field is the fixed field under higher derivations. In this paper we shall give an extension of his work about modular field extensions to modular integral domain extensions. Moreover, we shall prove that a modular extension is an extension that the derivation algebra is generated by components of higher derivations under some conditions. For example, in a finite extension of a field, a modular extension is characterized by the fact that the derivation algebra is generated by components of higher derivations.

References [Enhancements On Off] (What's this?)

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Keywords: High order derivations, higher derivations, separable extensions, purely inseparable extensions, modular extensions
Article copyright: © Copyright 1990 American Mathematical Society

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