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Title: Noncrossing partitions of an annulus (Extended abstract)
The noncrossing partition poset associated to a Coxeter group $$W$$ and Coxeter element $$c$$ is the interval $$[1,c]_T$$ in the absolute order on $$W$$. We construct a new model of noncrossing partititions for $$W$$ of classical affine type, using planar diagrams. The model in type $$\afftype{A}$$ consists of noncrossing partitions of an annulus. In type~$$\afftype{C}$$, the model consists of symmetric noncrossing partitions of an annulus or noncrossing partitions of a disk with two orbifold points. Following the lead of McCammond and Sulway, we complete $$[1,c]_T$$ to a lattice by factoring the translations in $$[1,c]_T$$, but the combinatorics of the planar diagrams leads us to make different choices about how to factor.  more » « less
Award ID(s):
2054489
PAR ID:
10530463
Author(s) / Creator(s):
;
Publisher / Repository:
The Séminaire Lotharingien de Combinatoire
Date Published:
ISSN:
1286-4889
Format(s):
Medium: X
Location:
https://www.mat.univie.ac.at/~slc/
Sponsoring Org:
National Science Foundation
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