English

Less than $2^{\omega}$ many translates of a compact nullset may cover the real line

Logic 2011-09-27 v1 Classical Analysis and ODEs

Abstract

We answer a question of Darji and Keleti by proving that there exists a compact set C0\RRC_0\subset\RR of measure zero such that for every perfect set P\RRP\subset\RR there exists x\RRx\in\RR such that (C0+x)P(C_0+x)\cap P is uncountable. Using this C0C_0 we answer a question of Gruenhage by showing that it is consistent with ZFCZFC (as it follows e.g. from cof(\iN)<2ω\textrm{cof}(\iN)<2^\omega) that less than 2ω2^\omega many translates of a compact set of measure zero can cover \RR\RR.

Keywords

Cite

@article{arxiv.1109.5307,
  title  = {Less than $2^{\omega}$ many translates of a compact nullset may cover the real line},
  author = {Márton Elekes and Juris Steprāns},
  journal= {arXiv preprint arXiv:1109.5307},
  year   = {2011}
}