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arXiv · 2310.04973

Tangent Weights and Invariant Curves in Type A Bow Varieties

Alexander O. Foster·Yiyan Shou
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Abstract

This paper provides a complete classification of torus-invariant curves in Cherkis bow varieties of type A. We develop combinatorial codes for compact and noncompact invariant curves involving the butterfly diagrams, Young diagrams, and binary contingency tables. As a key intermediate step, we also develop a novel tangent weight formula. Finally, we apply this new machinery to example bow varieties to demonstrate how to obtain their 1-skeletons (union of fixed points and invariant curves).

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Alexander O. Foster, Yiyan Shou. 2023-10-08. Tangent Weights and Invariant Curves in Type A Bow Varieties. https://doi.org/10.3842/sigma.2025.016

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