Legendrian knots and multi-crossings

Amit Kumar; Jake Murphy; Brian Naff

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arXiv · 2405.04724

Legendrian knots and multi-crossings

Amit Kumar·Jake Murphy·Brian Naff

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Abstract

It was shown in arXiv:1208.5742 that any smooth knot can be represented by an \"ubercrossing projection, i.e. a knot projection with no crossings aside from a single multi-crossing. We extend this idea to Legendrian knots and investigate \"ubercrossing and petal projections in the front and Lagrangian projections. We show that any Legendrian knot with an \"ubercrossing projection in the front projection is smoothly isotopic to the unknot and we demonstrate how to compute the $tb$ and rotation numbers for petal projections in the Lagrangian projection.

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BibTeX RIS

Amit Kumar, Jake Murphy, Brian Naff. 2024-05-08. Legendrian knots and multi-crossings. https://arxiv.org/abs/2405.04724

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