… However, since we consider general countable groups we have to be more careful, and
construct a prodense subgroup which possess the additional property that it is contained in …

… of countable primitive groups in several settings including linear groups, subgroups of
mapping class groups, groups acting minimally on trees and convergence groups. The latter …

… groups is said to be countably recognizable, if every group all of whose countable subgroups
are contained in countable -subgroups is itself an -group. Many examples of such classes …

We prove that every group ring of a non-abelian locally free group which is the union of an
ascending sequence of free groups is primitive. In particular, every group ring of a countable …

… Section 2 is dedicated to the classification of countable primitive groups that are not of … the
classification of countable primitive groups into three disjoint classes: primitive groups of affine…

… of the existence of countable B-groups is discussed. Three distinct methods are given to
embed a countable group as a regular subgroup of a simply primitive permutation group, and in …

… many co-finite subsets there are 2Xo moieties of ft; moreover, if G is a group of permutations
… a countably infinite set and G is a primitive group of permutations of ft that has no countable …

… abstract group Γ is primitive if it admits a faithful primitive action … Since each N < Γ has at
most countably many cosets we can … We shall construct ∆ to be a free group on countably many …

… group, the arithmetical complexity of various definable subsets of the group, and the extent
to which countable … Using the primitive generator zn of each field Fn, we define the elements …

… When analyzing countable primitive linear groups one quickly finds infinite counterparts to
many of the AOS categories. We describe infinite linear analogs for primitive groups of affine …