Coxeter-matrix criterion for Auslander regularity of 1-Gorenstein algebras

Determine whether a 1-Gorenstein algebra of finite global dimension with an admissible ordering of its simple modules is Auslander regular whenever the left triangular factor in a Bruhat decomposition of its Coxeter matrix is the identity.

Background

The paper proves for Auslander regular algebras that, with an admissible ordering, the Coxeter matrix has a Bruhat decomposition whose left triangular factor is the identity. Question 5.1 asks whether, under the weaker assumptions of 1-Gorensteinness and finite global dimension, the converse implication holds. An example shows that the 1-Gorenstein assumption cannot simply be omitted.

References

Question 5.1. Let A be a 1-Gorenstein algebra of finite global dimension with an admissible ordering of the simple modules and assume C has a Bruhat decomposition U1PU2 with U1 = id. Is A then Auslander regular?

Auslander regular algebras and Coxeter matrices  (2501.09447 - Klász et al., 16 Jan 2025) in Question 5.1, Section 5