3 papers
math.GR2026
Commutators of signed -cycles
Philipp Bader, Bernhard Böhmler, Patrick Wegener
We show that for each element of the commutator subgroup in the symmetric group resp. in the signed symmetric group $(\mathbb{Z}/2\mathbb{Z})^n\rtimes\m…
math.RA2026
A counterexample to Köthe's conjecture and a question of Rowen
Tom Adamczewski, Bernhard Böhmler, Rene Marczinzik
We construct a counterexample to Köthe's conjecture and use this to also answer a question due to Rowen.
math.AC2026
Tor and Ext vanishing results for commutative Artinian rings
Bernhard Böhmler, Rene Marczinzik
We give a negative answer to a question of Avramov, Buchweitz and Şega by constructing a commutative local finite-dimensional non-Gorenstein algebra with $\operatorname{Ext}_R^…