Product preservation and stable units for reflections into idempotent subvarieties

Authors

  • Joao J. Xarez CIDMA - Center for Research and Development in Mathematics and Applications, Department of Mathematics, University of Aveiro, Portugal.
Abstract:

We give a necessary and sufficient condition for the preservation of finite products by a reflection of a variety of universal algebras into an idempotent subvariety. It is also shown that simple and semi-left-exact reflections into subvarieties of universal algebras are the same. It then follows that a reflection of a variety of universal algebras into an idempotent subvariety has stable units if and only if it is simple and the above-mentioned condition holds.

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Journal title

volume 13  issue 1

pages  1- 22

publication date 2020-07-01

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