English

An analogue of Edmonds' Branching Theorem for infinite digraphs

Combinatorics 2020-04-06 v3

Abstract

We extend Edmonds' Branching Theorem to locally finite infinite digraphs. As examples of Oxley or Aharoni and Thomassen show, this cannot be done using ordinary arborescences, whose underlying graphs are trees. Instead we introduce the notion of pseudo-arborescences and prove a corresponding packing result. Finally, we verify some tree-like properties for these objects, but give also an example that their underlying graphs do in general not correspond to topological trees in the Freudenthal compactification of the underlying multigraph of the digraph.

Keywords

Cite

@article{arxiv.1805.02933,
  title  = {An analogue of Edmonds' Branching Theorem for infinite digraphs},
  author = {J. Pascal Gollin and Karl Heuer},
  journal= {arXiv preprint arXiv:1805.02933},
  year   = {2020}
}

Comments

15 pages, 1 figure; only minor changes to metadata