On a generalization of two results of Happel to commutative rings

Tony J. Puthenpurakal

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arXiv · 2208.12137

On a generalization of two results of Happel to commutative rings

Tony J. Puthenpurakal

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Abstract

In this paper we extend two results of Happel to commutative rings. Let $(A, \mathfrak{m})$ be a commutative Noetherian local ring. Let $D^b_f(mod \ A)$ be the bounded derived category of complexes of finitely generated modules over $A$ with finite length cohomology. We show $D^b_f( mod \ A)$ has Auslander-Reiten(AR)-triangles if and only if $A$ is regular. Let $K^b_f(proj \ A)$ be the homotopy category of finite complexes of finitely generated free $A$-modules with finite length cohomology. We show that if $A$ is complete and if $A$ is Gorenstein then $K^b_f( proj \ A)$ has AR triangles. Conversely we show that if $K^b_f(proj \ A)$ has AR triangles and if $A$ is Cohen-Macaulay or if $\dim A = 1$ then $A$ is Gorenstein.

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Tony J. Puthenpurakal. 2022-08-25. On a generalization of two results of Happel to commutative rings. https://arxiv.org/abs/2208.12137

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