Secondary invariants for Frechet algebras and quasihomomorphisms.
Some algebraic aspects of quadratic forms over fields of characteristic two.
Splitting obstructions and properties of objects in the Nil categories
We show that the objects of Bass-Farrell categories which represent 0 in the corresponding Nil groups are precisely those which are stably triangular. This extends to Waldhausen's Nil group of the amalgamated free product with index 2 factors. Applications include a description of Cappell's special UNil group and reformulations of those splitting and fibering theorems which use the Nil groups.
Stable short exact sequences and the maximal exact structure of an additive category
It was recently proved that every additive category has a unique maximal exact structure, while it remained open whether the distinguished short exact sequences of this canonical exact structure coincide with the stable short exact sequences. The question is answered by a counterexample which shows that none of the steps to construct the maximal exact structure can be dropped.
Strictification of categories weakly enriched in symmetric monoidal categories.
Symbol lengths in Milnor -theory.
Symmetric monoidal categories model all connective spectra.