Problems / algebra
algebra / Representation theory of algebras; homological conjectures
The Auslander-Reiten conjecture for Artin algebras
Claims Theorem 1.1: over k=F2(q,H1,H2) there are a finite-dimensional triangular algebra Λ with eight simple modules and rad(Λ)4=0, and a finite-dimensional nonprojective Gorenstein-projective module Z with Exti(Z,Z)=Exti(Z,Λ)=0 for all i≥1, persisting under every field extension (so also over an algebraically closed field of characteristic two). This disproves the Auslander-Reiten and Gorenstein-projective conjectures; Z⊕Λ also refutes the generator form. It does NOT touch the commutative Noetherian form of the conjecture, and gives no example in characteristic zero.