Hypothesis: HR 231:
\(UT(WO,WO,WO)\): The union of a well ordered collection of well orderable sets is well orderable.
Conclusion: HR 273:
There is a subset of \({\Bbb R}\) which is not Borel.
List of models where hypothesis is true and the conclusion is false:
| Name | Statement |
|---|---|
| \(\cal M12(\aleph)\) Truss' Model I | This is a variation of Solovay's model, <a href="/models/Solovay-1">\(\cal M5(\aleph)\)</a> in which \(\aleph\) is singular |
Code: 3
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