Extension algebras of standard modules

Abstract

Let $A$ be a finite dimensional $k$-algebra standardly stratified for a partial order $⩽$ and $\Delta$ be the direct sum of all standard modules. In this paper we study the extension algebra $E={\text{Ext}}_A^{\ast }(\Delta ,\Delta )$ of standard modules, characterize the stratification property of $E$ for $⩽$ and ${⩽}^{op}$, and obtain a sufficient condition for $E$ to be a generalized Koszul algebra (in a sense which we define).

The final version accepted by Comm. Algebra

References in corpus (1)

• Algebras stratified for all linear orders

Cited by in corpus (1)

• A generalized Koszul theory and its application