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arXiv · 2510.13764

The minimal Rickard complexes of braids on two strands

Abstract

The Rickard complex of a braid with strands colored by positive integers is a chain complex of singular Soergel bimodules. The complex determines the colored triply-graded homology and colored sl(N) homology of the braid closure, when closure is color-compatible. For each braid on two strands with any colors, we construct a minimal complex that is homotopy equivalent to its Rickard complex. It is not obtained by laborious simplification; instead, it is defined directly by explicit formulas obtained by educated guesswork and reverse engineering.

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BibTeXRIS

Joshua Wang. 2026-04-20. The minimal Rickard complexes of braids on two strands. https://arxiv.org/abs/2510.13764

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