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Abelian extensions of algebras in congruence-modular varieties

William H. Rowan
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Abstract

We define abelian extensions of algebras in congruence-modular varieties. The theory is sufficiently general that it includes, in a natural way, extensions of R-modules for a ring R. We also define a cohomology theory, which we call clone cohomology, such that the cohomology group in dimension one is the group of equivalence classes of extensions.

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William H. Rowan. 2000-05-13. Abelian extensions of algebras in congruence-modular varieties. https://arxiv.org/abs/math/0005134

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