Cluster-tilted algebras as trivial extensions

Assem, Ibrahim; Brüstle, Thomas; Schiffler, Ralf

Cluster-tilted algebras as trivial extensions

Authors

Assem, Ibrahim

Brüstle, Thomas

Schiffler, Ralf

Description

Given a finite dimensional algebra $C$ (over an algebraically closed field) of global dimension at most two, we define its relation-extension algebra to be the trivial extension $C\ltimes \Ext_C^2(DC,C)$ of $C$ by the $C$-$C$-bimodule $\Ext_C^2(DC,C)$. We give a construction for the quiver of the relation-extension algebra in case the quiver of $C$ has no oriented cycles. Our main result says that an algebra $\tilde C$ is cluster-tilted if and only if there exists a tilted algebra $C$ such that $\tilde C$ is isomorphic to the relation-extension of $C$.
14 pages