# A remark on $\varepsilon$-maps in dimension 1

**Authors:** T. Tam Nguyen Phan

arXiv: 1907.12063 · 2019-07-30

## TL;DR

This paper investigates whether certain surjective maps from the circle to a graph, with small pre-image diameters, can be decomposed as free factors in the fundamental group, exploring properties of epsilon-maps in one dimension.

## Contribution

It examines conditions under which epsilon-maps from the circle to a graph split as free factors in the fundamental group, providing insights into their algebraic and topological structure.

## Key findings

- Identifies conditions for epsilon-maps to split as free factors.
- Establishes bounds on epsilon for such splittings.
- Provides examples and counterexamples related to epsilon-maps.

## Abstract

Let $f\colon \mathbb{S}^1\rightarrow G$ be a surjective map from the standard unit circle to a graph $G$ such that the pre-image of each point has diameter less than $\varepsilon$. If $\varepsilon$ is small enough, does $f$ split as a free factor in $\pi_1(G)$?

## Full text

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## Figures

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## References

2 references — full list in the complete paper: https://tomesphere.com/paper/1907.12063/full.md

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Source: https://tomesphere.com/paper/1907.12063