Spatial graph as connected sum of a planar graph and a braid

Valeriy G. Bardakov; Akio Kawauchi

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arXiv · 2006.16072

Spatial graph as connected sum of a planar graph and a braid

Valeriy G. Bardakov·Akio Kawauchi

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Abstract

In this paper we show that every finite spatial graph is a connected sum of a planar graph, which is a forest, i.e. disjoint union of finite number of trees and a tangle. As a consequence we get that any finite spatial graph is a connected sum of a planar graph and a braid. Using these decompositions it is not difficult to find a set of generators and defining relations for the fundamental group of compliment of a spatial graph in 3-space $\mathbb{R}^3$.

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Valeriy G. Bardakov, Akio Kawauchi. 2020-06-29. Spatial graph as connected sum of a planar graph and a braid. https://arxiv.org/abs/2006.16072

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