3 papers
math.KT2025
The 2-torsion in the Farrell--Tate cohomology of PSL(4,Z), and torsion subcomplex reduction via discrete Morse theory
Alexander D. Rahm, Anh Tuan Bui, Matthias Wendt
In the present paper, we use discrete Morse theory to provide a new implementation of torsion subcomplex reduction for arithmetic groups. This leads both to a simpler algorithm as…
math.AT2024
4-torsion classes in the integral cohomology of oriented Grassmannians
Ákos K. Matszangosz, Matthias Wendt
We investigate the existence of 4-torsion in the integral cohomology of oriented Grassmannians. We prove a general criterion for the appearance of 4-torsion classes based on (twist…
math.AT2023
The mod 2 cohomology rings of oriented Grassmannians via Koszul complexes
Ákos K. Matszangosz, Matthias Wendt
We study the structure of mod 2 cohomology rings of oriented Grassmannians of oriented -planes in . Our main focus is on the struc…