3 papers
math.AC2026
When are permutation invariants Cohen-Macaulay?
H. E. A. Campbell, David L. Wehlau
Over a field of characteristic 0, every ring of invariants of a finite group is Cohen-Macaulay. This is not true for fields of positive characteristic. We consider permutation repr…
math.AC2026
Invariants of Finite Orthogonal Groups of Plus Type in Odd Characteristic
H. E. A. Campbell, R. James Shank, David L. Wehlau
We describe the rings of invariants for the finite orthogonal groups of plus type in odd characteristic acting on the defining representations. We also describe the invariants of t…
math.AC2025
Invariants of the finite orthogonal groups in odd dimension and even characteristic
H. E. A. Campbell, R. J. Shank, D. L. Wehlau
We describe the ring of invariants for the finite orthogonal groups in odd dimension and even characteristic acting on the defining representation. We construct a minimal algebra g…