English

Large free sets in universal algebras

Logic 2014-12-04 v3 Rings and Algebras

Abstract

We prove that for each universal algebra (A,A)(A,\mathcal A) of cardinality A2|A|\ge 2 and an infinite set XX of cardinality XA|X|\ge|\mathcal A|, the XX-th power (AX,AX)(A^X,\mathcal A^X) of the algebra (A,A)(A,\mathcal A) contains a free subset FAX\mathcal F\subset A^X of cardinality F=2X|\mathcal F|=2^{|X|}. This generalizes the classical Fichtenholtz-Kantorovitch-Hausdorff result on the existence of an independent family IP(X)\mathcal I\subset\mathcal P(X) of cardinality I=P(X)|\mathcal I|=|\mathcal P(X)| in the Boolean algebra P(X)\mathcal P(X) of subsets of an infinite set XX.

Cite

@article{arxiv.1209.6444,
  title  = {Large free sets in universal algebras},
  author = {Taras Banakh and Artur Bartoszewicz and Szymon Głab},
  journal= {arXiv preprint arXiv:1209.6444},
  year   = {2014}
}

Comments

4 pages

R2 v1 2026-06-21T22:12:38.215Z