4 papers
Universal localization of triangular matrix rings
Desmond Sheiham
If R is a triangular 2x2 matrix ring, the columns, P and Q, are projective left R-modules. We describe the universal localization of R which makes invertible an R-module morphism P…
Whitehead Groups of Localizations and the Endomorphism Class Group
Desmond Sheiham
We compute the Whitehead groups of the associative rings in a class which includes (twisted) formal power series rings and the augmentation localizations of group rings and polynom…
Invariants of Boundary Link Cobordism
Desmond Sheiham
An n-dimensional μ-component boundary link is a codimension 2 embedding of spheres L=\bigsqcup_μS^n \subset S^{n+2} such that there exist μdisjoint oriented embedded (n+1)-manifold…
Non-commutative Characteristic Polynomials and Cohn Localization
Desmond Sheiham
Almkvist proved that for a commutative ring A the characteristic polynomial of an endomorphism α:P \to P of a finitely generated projective A-module determines (P,α) up to extensio…