Hypersubstitutions M-Hyperidentity M-Solid Subvarieties of Semigroups
Institute of Mathematics and Informatics Bulgarian Academy of Sciences
Serdica Mathematical Journal, Vol. 23, No 1, (1997), 25p-34p
The basic concepts are M -hyperidentities, where M is a monoid
of hypersubstitutions. The set of all M -solid varieties of semigroups forms
a complete sublattice of the lattice of all varieties of semigroups. We fix
some specific varieties V of commutative semigroups and study the set of all
M -solid subvarieties of V , in particular, if V is nilpotent.
∗ The research of the author was supported by the Alexander v. Humboldt-Stiftung.