On weakly positive unit forms.
On wings of the Auslander-Reiten quivers of selfinjective algebras
We give necessary and sufficient conditions for a wing of an Auslander-Reiten quiver of a selfinjective algebra to be the wing of the radical of an indecomposable projective module. Moreover, a characterization of indecomposable Nakayama algebras of Loewy length ≥ 3 is obtained.
One point extensions of trees and quadratic forms
One-directed indecomposable pure injective modules over string algebras
We classify one-directed indecomposable pure injective modules over finite-dimensional string algebras.
Orbit algebras and periodicity
Given an object in a category, we study its orbit algebra with respect to an endofunctor. We show that if the object is periodic, then its orbit algebra modulo nilpotence is a polynomial ring in one variable. This specializes to a result on Ext-algebras of periodic modules over Gorenstein algebras. We also obtain a criterion for an algebra to be of wild representation type.
Orbit algebras that are invariant under stable equivalences of Morita type
In this note we show that there are a lot of orbit algebras that are invariant under stable equivalences of Morita type between self-injective algebras. There are also indicated some links between Auslander-Reiten periodicity of bimodules and noetherianity of their orbit algebras.
Orthodox bands of modules
Partial flag varieties and preprojective algebras
Let be a preprojective algebra of type , and let be the corresponding semisimple simply connected complex algebraic group. We study rigid modules in subcategories for an injective -module, and we introduce a mutation operation between complete rigid modules in . This yields cluster algebra structures on the coordinate rings of the partial flag varieties attached to .
Path coalgebras of profinite bound quivers, cotensor coalgebras of bound species and locally nilpotent representations
We prove that the study of the category C-Comod of left comodules over a K-coalgebra C reduces to the study of K-linear representations of a quiver with relations if K is an algebraically closed field, and to the study of K-linear representations of a K-species with relations if K is a perfect field. Given a field K and a quiver Q = (Q₀,Q₁), we show that any subcoalgebra C of the path K-coalgebra K◻Q containing is the path coalgebra of a profinite bound quiver (Q,), and the category C-Comod...
Peak reductions and waist reflection functors
Perfect Elements in the Free Modular Lattices.
Periodicity and representation type of modular Lie algebras.
Piecewise hereditary algebras under field extensions
Let be a finite-dimensional -algebra and be a finite separable field extension. We prove that is derived equivalent to a hereditary algebra if and only if so is .
Polynomial functors over finite fields
Polynomial growth trivial extensions of simply connected algebras
Polynomial invariants of representations of quivers.
Positivity in coefficient-free rank two cluster algebras.
Präradikale und Endomorphismenringe von Moduln.
Preface, Contents, List of Participants
Preprojective Components of Wild Tilted Algebras.