English

Finite powers of selectively pseudocompact groups

General Topology 2017-06-16 v1

Abstract

A space XX is called {\it selectively pseudocompact} if for each sequence (Un)nN(U_{n})_{n\in \mathbb{N}} of pairwise disjoint nonempty open subsets of XX there is a sequence (xn)nN(x_{n})_{n\in \mathbb{N}} of points in XX such that clX({xn:n<ω})(n<ωUn)cl_X(\{x_n : n < \omega\}) \setminus \big(\bigcup_{n < \omega}U_n \big) \neq \emptyset and xnUnx_{n}\in U_{n}, for each n<ωn < \omega. Countably compact space spaces are selectively pseudocompact and every selectively pseudocompact space is pseudocompact. We show, under the assumption of CHCH, that for every positive integer k>2k > 2 there exists a topological group whose kk-th power is countably compact but its (k+1)(k+1)-st power is not selectively pseudocompact. This provides a positive answer to a question posed in \cite{gt} in any model of ZFC+CHZFC+CH.

Keywords

Cite

@article{arxiv.1706.04911,
  title  = {Finite powers of selectively pseudocompact groups},
  author = {S. Garcia-Ferreira and A. H. Tomita},
  journal= {arXiv preprint arXiv:1706.04911},
  year   = {2017}
}
R2 v1 2026-06-22T20:19:50.402Z