Mutation Cycles from Reddening Sequences
Tucker J. Ervin, Scott Neville
TL;DR
This work investigates how reddening sequences can be leveraged to generate mutation cycles in quiver mutation. By forming triangular extensions $Q = T \stackrel{A}{\rightarrow} H$ from two quivers with reddening sequences and concatenating these sequences, the authors obtain mutation cycles via $\mu_{\\mathbf M_T\\mathbf M_H}(Q)$, with exact equality or isomorphism indicating cycles. They establish conditions under which the cycles are simple using C-matrix-based distinguishability and analyze reddening sequences in forkless parts, including classifications in low rank for abundant acyclic quivers and keys. The results provide a versatile construction toolkit for producing many mutation cycles, offering new fully generic families, explicit long cycles, and non-extension examples, thereby enriching the understanding of cluster automorphisms and mutation equivalence in cluster algebras.
Abstract
Given two quivers, each with a reddening sequence, we show how to construct a plethora of mutation cycles. We give several examples, including a generalization of the construction of long mutation cycles in earlier work by the second author. We also give new results on the reddening sequences of certain mutation-acyclic quivers and forks, classifying them in some cases.
