English

What is actually a metric graph?

Combinatorics 2021-03-17 v2 Functional Analysis General Topology

Abstract

Metric graphs are often introduced based on combinatorics, upon "associating" each edge of a graph with an interval; or else, casually "gluing" a collection of intervals at their endpoints in a network-like fashion. Here we propose an abstract, self-contained definition of metric graph. Being mostly topological, it doesn't require any knowledge from graph theory and already determines uniquely several concepts that are commonly and unnecessarily \textit{defined} in the literature. Nevertheless, many ideas mentioned here are folklore in the quantum graph community: we discuss them for later reference.

Keywords

Cite

@article{arxiv.1912.07549,
  title  = {What is actually a metric graph?},
  author = {Delio Mugnolo},
  journal= {arXiv preprint arXiv:1912.07549},
  year   = {2021}
}
R2 v1 2026-06-23T12:47:27.531Z