# ALGEBRAIC COMBINATORICS

A combinatorial approach to scattering diagrams
Algebraic Combinatorics, Volume 3 (2020) no. 3, pp. 603-636.

Scattering diagrams arose in the context of mirror symmetry, but a special class of scattering diagrams (the cluster scattering diagrams) were recently developed to prove key structural results on cluster algebras. We use the connection to cluster algebras to calculate the function attached to the limiting wall of a rank-2 cluster scattering diagram of affine type. In the skew-symmetric rank-2 affine case, this recovers a formula due to Reineke. In the same case, we show that the generating function for signed Narayana numbers appears in a role analogous to a cluster variable. In acyclic finite type, we construct cluster scattering diagrams of acyclic finite type from Cambrian fans and sortable elements, with a simple direct proof.

Revised: 2019-09-03
Accepted: 2019-12-28
Published online: 2020-06-02
DOI: https://doi.org/10.5802/alco.107
Classification: 13F60,  14N35,  05E10,  05A15,  20F55
Keywords: Cluster algebra, cluster scattering diagram, root system, Narayana number, exchange matrix, Cambrian fan, broken line.
@article{ALCO_2020__3_3_603_0,
title = {A combinatorial approach to scattering diagrams},
journal = {Algebraic Combinatorics},
publisher = {MathOA foundation},
volume = {3},
number = {3},
year = {2020},
pages = {603-636},
doi = {10.5802/alco.107},
language = {en},
url = {alco.centre-mersenne.org/item/ALCO_2020__3_3_603_0/}
}
Reading, Nathan. A combinatorial approach to scattering diagrams. Algebraic Combinatorics, Volume 3 (2020) no. 3, pp. 603-636. doi : 10.5802/alco.107. https://alco.centre-mersenne.org/item/ALCO_2020__3_3_603_0/

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