Categorifications of noncrossing partitions of type B and affine type A

Yiyu Cheng

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arXiv · 2611.00966

Categorifications of noncrossing partitions of type B and affine type A

Yiyu Cheng

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Abstract

The lattice of wide subcategories of a tube is isomorphic to the lattice of noncrossing partitions of type B. We prove that through this categorification of noncrossing partitions, Kreweras complement is taking left perpendicular categories. With the help of this categorification and weighted projective lines, we obtain an inclusion from the lattice of noncrossing partitions of type B_n to a lattice of affine type A_n which preserves Kreweras complement.

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Yiyu Cheng. 2026-10-31. Categorifications of noncrossing partitions of type B and affine type A. https://arxiv.org/abs/2611.00966

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