Coset posets of infinite groups

Coset and double-coset decompositions of the magnetic point groups.

The coset and double-coset decompositions of the 420 subgroups of m(z)3(xyz)m(xy)1' (O(h)1') and the 236 subgroups of 6(z)/m(z)m(x)m(1)1' (D(6h)1') with respect to each of their subgroups are calculated along with additional mathematical properties of these groups.

Coset Intersection Graphs for Groups

Let H,K be subgroups of G. We investigate the intersection properties of left and right cosets of these subgroups. If H and K are subgroups of G, then G can be partitioned as the disjoint union of all left cosets of H, as well as the disjoint union of all right cosets of K. But how do these two partitions of G intersect each other? Definition 1. Let G be a group, and H a subgroup of G. A left t...

Automorphism groups of finite posets

For any finite group G, we construct a finite poset (or equivalently, a finite T0-space) X, whose group of automorphisms is isomorphic to G. If the order of the group is n and it has r generators, X has n(r+2) points. This construction improves previous results by G. Birkhoff and M.C. Thornton. The relationship between automorphisms and homotopy types is also analyzed.

Infinite Series-Parallel Posets: Logic and Languages

We show that a set of uniformly width-bounded infinite seriesparallel pomsets is ω-series-rational iff it is axiomatizable in monadic second order logic iff it is ω-recognizable. This extends recent work by Lodaya and Weil on sets of finite series-parallel pomsets in two aspects: It relates their notion of series-rationality to logical concepts, and it generalizes the equivalence of recognizabi...

Topological Dynamics in Coset Transformation Groups