arXiv · 1611.08152
A Q-set is an uncountable set of reals all of whose subsets are relative $G_\delta$ sets. We prove that, for an arbitrary uncountable cardinal kappa, there is consistently a Q-set of size $\kappa$ whose square is not Q. This answers a question of A. Miller.
Joerg Brendle. 2016-11-24. Q. https://arxiv.org/abs/1611.08152
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