# Classifying $\tau$-tilting modules over the Auslander algebra of $K[x]/(x^n)$

Research paper by Osamu Iyama, Xiaojin Zhang

Indexed on: 16 Feb '16Published on: 16 Feb '16Published in: Mathematics - Representation Theory

#### Abstract

We build a bijection between the set $\sttilt\Lambda$ of isomorphism classes of basic support $\tau$-tilting modules over the Auslander algebra $\Lambda$ of $K[x]/(x^n)$ and the symmetric group $\mathfrak{S}_{n+1}$, which is an anti-isomorphism of partially ordered sets with respect to the generation order on $\sttilt\Lambda$ and the left order on $\mathfrak{S}_{n+1}$. This restricts to the bijection between the set $\tilt\Lambda$ of isomorphism classes of basic tilting $\Lambda$-modules and the symmetric group $\mathfrak{S}_n$ due to Br\"{u}stle, Hille, Ringel and R\"{o}hrle. Regarding the preprojective algebra $\Gamma$ of Dynkin type $A_n$ as a factor algebra of $\Lambda$, we show that the tensor functor $-\otimes_{\Lambda}\Gamma$ induces a bijection between $\sttilt\Lambda\to\sttilt\Gamma$. This recover Mizuno's bijection $\mathfrak{S}_{n+1}\to\sttilt\Gamma$ for type $A_n$.