Abstract:
We consider some questions on covers in the lattice of varieties of $m$-groups. We prove the existence of a nonabelian cover of the smallest nontrivial variety of $m$-groups. We show that there exists an uncountable set of o-approximable varieties of $m$-groups each of which has continuum many o-approximable covers. In the lattice of o-approximable varieties of $m$-groups we find a variety that has no covers in this variety and no independent basis of identities.