On the structure of equationally complete varieties. II

Author:
Don Pigozzi

Journal:
Trans. Amer. Math. Soc. **264** (1981), 301-319

MSC:
Primary 08B05; Secondary 18C05

MathSciNet review:
603765

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Abstract: Each member of a large family of nonassociative or, when applicable, nondistributive varieties has the following universal property: Every variety that satisfies certain very weak versions of the amalgamation and joint embedding properties is isomorphic, as a category, to a coreflective subcategory of some equationally complete subvariety of . Moreover, the functor which serves to establish the isomorphism preserves injections. As a corollary one obtains the existence of equationally complete subvarieties of that fail to have the amalgamation property and fail to be residually small. The family of varieties universal in the above sense includes commutative groupoids, bisemigroups (i.e., algebras with two independent associative operations), and quasi-groups.

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DOI:
https://doi.org/10.1090/S0002-9947-1981-0603765-1

Article copyright:
© Copyright 1981
American Mathematical Society