Unknottability of spatial graphs by region crossing changes

Yukari Funakoshi; Kenta Noguchi; Ayaka Shimizu

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arXiv · 2009.12119

Unknottability of spatial graphs by region crossing changes

Yukari Funakoshi·Kenta Noguchi·Ayaka Shimizu

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Abstract

A region crossing change is a local transformation on spatial graph diagrams switching the over/under relations at all the crossings on the boundary of a region. In this paper, we show that a spatial graph of a planar graph is unknottable by region crossing changes if and only if the spatial graph is non-Eulerian or is Eulerian and proper.

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Yukari Funakoshi, Kenta Noguchi, Ayaka Shimizu. 2020-09-25. Unknottability of spatial graphs by region crossing changes. https://arxiv.org/abs/2009.12119

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