Paper detail

Algebra in superextensions of twinic groups

Given a group $X$ we study the algebraic structure of the compact right-topological semigroup $λ(X)$ consisting of maximal linked systems on $X$. This semigroup contains the semigroup $β(X)$ of ultrafilters as a closed subsemigroup. We construct a faithful representation of the semigroup $λ(X)$ in the semigroup of all self-maps of the power-set of $X$ and using this representation describe the structure of minimal ideal and minimal left ideals of $λ(X)$ for each twinic group $X$. The class of twinic groups includes all amenable groups and all groups with periodic commutators but does not include the free group with two generators.