Cubes, cacti, and framed long knots

Robin Koytcheff; Yongheng Zhang

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arXiv · 2301.08858

Cubes, cacti, and framed long knots

Robin Koytcheff·Yongheng Zhang

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Abstract

We define an action of the operad of projective spineless cacti on each stage of the Taylor tower for the space of framed 1-dimensional long knots in any Euclidean space. By mapping a subspace of the overlapping intervals operad to the subspace of normalized cacti, we prove a space-level compatibility of our action with Budney's little 2-cubes action on the space of framed long knots itself. Our result improves upon previous joint work of the first author related to the conjecture that the Taylor tower for classical long knots is a universal Vassiliev invariant over the integers. As a corollary, we reprove the nontriviality of a certain Browder bracket class first detected by Sakai.

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Robin Koytcheff, Yongheng Zhang. 2023-01-21. Cubes, cacti, and framed long knots. https://arxiv.org/abs/2301.08858

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