## Algebra & Number Theory

### Singularities of locally acyclic cluster algebras

#### Abstract

We show that locally acyclic cluster algebras have (at worst) canonical singularities. In fact, we prove that locally acyclic cluster algebras of positive characteristic are strongly $F$-regular. In addition, we show that upper cluster algebras are always Frobenius split by a canonically defined splitting, and that they have a free canonical module of rank one. We also give examples to show that not all upper cluster algebras are $F$-regular if the local acyclicity is dropped.

#### Article information

Source
Algebra Number Theory, Volume 9, Number 4 (2015), 913-936.

Dates
Revised: 12 January 2015
Accepted: 18 March 2015
First available in Project Euclid: 16 November 2017

https://projecteuclid.org/euclid.ant/1510842340

Digital Object Identifier
doi:10.2140/ant.2015.9.913

Mathematical Reviews number (MathSciNet)
MR3352824

Zentralblatt MATH identifier
1350.13017

#### Citation

Benito, Angélica; Muller, Greg; Rajchgot, Jenna; Smith, Karen E. Singularities of locally acyclic cluster algebras. Algebra Number Theory 9 (2015), no. 4, 913--936. doi:10.2140/ant.2015.9.913. https://projecteuclid.org/euclid.ant/1510842340

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