The fundamental groups of subsets of closed surfaces inject into their first shape groups.
The genus problem for one-relator products of locally indicable groups.
The geometric invariants of direct products of virtually free groups.
The geometry of abstract groups and their splittings.
A survey of splitting theorems for abstract groups and their applications. Topics covered include preliminaries, early results, Bass-Serre theory, the structure of G-trees, Serre's applications to SL2 and length functions. Stallings' theorem, results about accessibility and bounds for splittability. Duality groups and pairs; results of Eckmann and collaborators on PD2 groups. Relative ends, the JSJ theorems and the splitting results of Kropholler and Roller on PDn groups. Notions of quasi-isometry,...
The groupoid of varieties of idempotent semigroups.
The Grushko decomposition of a finite graph of finite rank free groups: an algorithm.
The holomorphic automorphism group of the complex disk.
The homology of Peiffer products of groups.
The homomorphic images of infinite symmetric groups.
The irreducible six-dimensional complex representations of that are nontrivial on .
The Isomorphism Problem for One-relator Groups with Non-trivial Centre.
The isomorphism problem for toral relatively hyperbolic groups
We provide a solution to the isomorphism problem for torsion-free relatively hyperbolic groups with abelian parabolics. As special cases we recover solutions to the isomorphism problem for: (i) torsion-free hyperbolic groups (Sela, [60] and unpublished); and (ii) finitely generated fully residually free groups (Bumagin, Kharlampovich and Miasnikov [14]). We also give a solution to the homeomorphism problem for finite volume hyperbolic -manifolds, for . In the course of the proof of the main result,...
The Jacobson radical of edomorphism rings of totally projective groups of finite type.
The Johnson homomorphism and the second cohomology of .
The Lattice automorphisms of simple algebraic groups over F2.
The lattice of solid -subgroups of a retractable group
The local finiteness of some groups generated by a conjugacy class of order 3 elements.
The Lower Central Series of a Join of Subnormal Subgroups.
The lower central series of the free partially commutative group.
The lower garland of subgroup lattices in linear groups.