English

Topological Tournaments

Dynamical Systems 2023-04-04 v1

Abstract

A directed graph RR^{\circ} on a set XX is a set of ordered pairs of distinct points called \emph{arcs}. It is a tournament when every pair of distinct points is connected by an arc in one direction or the other (and not both). We can describe a tournament RX×XR \subset X \times X as a total, antisymmetric relation, i.e. RR1=X×XR \cup R^{-1} = X \times X and RR1R \cap R^{-1} is the diagonal 1X={(x,x):xX}1_X = \{ (x,x) : x \in X \}. The set of arcs is R=R1X=(X×X)R1R^{\circ} = R \setminus 1_X = (X \times X) \setminus R^{-1}. A topological tournament on a compact Hausdorff space XX is a tournament RR which is a closed subset of X×XX \times X. We construct uncountably many non-isomorphic examples on the Cantor set XX as well as examples of arbitrarily large cardinality. We also describe compact Hausdorff spaces which do not admit any topological tournament.

Keywords

Cite

@article{arxiv.2304.00055,
  title  = {Topological Tournaments},
  author = {Ethan Akin},
  journal= {arXiv preprint arXiv:2304.00055},
  year   = {2023}
}
R2 v1 2026-06-28T09:43:53.127Z