M. Schmidmeier

collaborators

3 papers

math.RT2025

Gorenstein-Projective Modules over the Ring of Dual Integers

Xiu-Hua Luo, Markus Schmidmeier

The ring of dual integers is the bounded polynomial ring $Z [I^µ] = Z [T] / (T^{2})$ with integer coefficients. We describe the (finitely generated) Gorenstein-projective $\…

math.GR2025

Abelian p-groups with a fixed elementary subgroup or with a fixed elementary quotient

Justyna Kosakowska, Markus Schmidmeier, Martin Schreiner

In his 1934 paper, G.\ Birkhoff poses the problem of classifying pairs $(G, U)$ where $G$ is an abelian group and $U \subset G$ a subgroup, up to automorphisms of $G$ . In general, Bi…

math.RT2025

Invariant Subspaces of Nilpotent Operators. Level, Mean, and Colevel: The Triangle $T (n)$

Claus Michael Ringel, Markus Schmidmeier

We consider the category $S (n)$ of all pairs $X = (U, V)$ , where $V$ is a finite-dimensional vector space with a nilpotent operator $T$ with $T^{n} = 0$ , and $U$ is a subspac…

Gorenstein-Projective Modules over the Ring of Dual Integers

Abelian p-groups with a fixed elementary subgroup or with a fixed elementary quotient

Invariant Subspaces of Nilpotent Operators. Level, Mean, and Colevel: The Triangle T(n)

Invariant Subspaces of Nilpotent Operators. Level, Mean, and Colevel: The Triangle $T (n)$