English

A game-theoretic proof of Shelah's theorem on labeled trees

Logic 2019-08-08 v1

Abstract

We give a new proof of a theorem of Shelah which states that for every family of labeled trees, if the cardinality κ\kappa of the family is much larger (in the sense of large cardinals) than the cardinality λ\lambda of the set of labels, more precisely if the partition relation κ(ω)λ<ω\kappa \to (\omega)^{\mathord{<}\omega}_\lambda holds, then there is a homomorphism from one labeled tree in the family to another. Our proof uses a characterization of such homomorphisms in terms of games.

Cite

@article{arxiv.1908.02442,
  title  = {A game-theoretic proof of Shelah's theorem on labeled trees},
  author = {Trevor M. Wilson},
  journal= {arXiv preprint arXiv:1908.02442},
  year   = {2019}
}