Less than $2^{\omega}$ many translates of a compact nullset may cover the real line
Abstract
We answer a question of Darji and Keleti by proving that there exists a compact set $C_0\subset\RR$ of measure zero such that for every perfect set $P\subset\RR$ there exists $x\in\RR$ such that $(C_0+x)\cap P$ is uncountable. Using this $C_0$ we answer a question of Gruenhage by showing that it is consistent with $ZFC$ (as it follows e.g. from $\textrm{cof}(\iN)<2^\omega$) that less than $2^\omega$ many translates of a compact set of measure zero can cover $\RR$.
- Publication:
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arXiv e-prints
- Pub Date:
- September 2011
- DOI:
- 10.48550/arXiv.1109.5307
- arXiv:
- arXiv:1109.5307
- Bibcode:
- 2011arXiv1109.5307E
- Keywords:
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- Mathematics - Logic;
- Mathematics - Classical Analysis and ODEs;
- Primary 28E15;
- Secondary 03E17;
- 03E35
- E-Print:
- Fund. Math. 181 (2004), no. 1, 89-96