On the Wu invariants for immersions of a graph into the plane

Ryo Nikkuni

doi:10.4310/hha.2010.v12.n1.a5

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arXiv · 0908.3109

On the Wu invariants for immersions of a graph into the plane

Ryo Nikkuni

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Abstract

We give an explicit calculation of the Wu invariants for immersions of a finite graph into the plane and classify all generic immersions of a graph into the plane up to regular homotopy by the Wu invariant. This result is a generalization of the fact that two plane curves are regularly homotopic if and only if they have the same rotation number.

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Ryo Nikkuni. 2009-08-21. On the Wu invariants for immersions of a graph into the plane. https://doi.org/10.4310/hha.2010.v12.n1.a5

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