Absolute subretracts and weak injectives in congruence modular varieties

Davey, Brian A.; Kovács, L. G.

doi:10.1090/S0002-9947-1986-0849474-X

Absolute subretracts and weak injectives in congruence modular varieties
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by Brian A. Davey and L. G. Kovács PDF

Trans. Amer. Math. Soc. 297 (1986), 181-196 Request permission

Abstract:

Absolute subretracts and weak injectives in congruence modular varieties of universal algebras are investigated by focusing attention on the directly indecomposibles. The proofs rely on a congruence modular version of generalized direct products (direct products with amalgamation) and on the generalized Jónsson Lemma for congruence modular varieties. The results have immediate application to varieties of groups or rings.

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