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Can the Collatz conjecture be independent of ZFC? [closed]

It is known that the Continuum Hypothesis is independent of ZFC. The formulation of the Collatz conjecture looks somehow more simple than that of the Continuum Hypothesis. Is it possible that the ...
Riemann's user avatar
  • 654
1 vote
1 answer
121 views

CH and the existence of a Borel partition of small cardinality

Say $\kappa$ is small if any set of cardinality $\kappa$ has outer-Lebesgue measure zero. We know that, in the Cohen model of ZFC where CH is false, there is a Borel partition of the unit interval of ...
Y.Z.'s user avatar
  • 231
6 votes
1 answer
626 views

Can $H_{\omega_1}$ and $H_{\omega_2}$ be in bi-interpretation synonymy?

This question concerns the possibility of the bi-interpretation synonymy of the structure $\langle H_{\omega_1},\in\rangle$, consisting of the hereditarily countable sets, and the structure $\langle ...
Joel David Hamkins's user avatar
33 votes
1 answer
2k views

Is it still an open problem whether $\mathbb{R}^\omega$ is normal in the box topology?

On page 205 of his Topology textbook, James Munkres made an interesting remark: It is not known whether $\mathbb{R}^\omega$ is normal in the box topology. Mary-Ellen Rudin has shown that the answer ...
Keshav Srinivasan's user avatar