Hypothesis: HR 128:

Aczel's Realization Principle: On every infinite set there is a Hausdorff topology with an infinite set of non-isolated points.

Conclusion: HR 299:

Any extremally disconnected compact Hausdorff space is projective in the category of Boolean topological spaces.

List of models where hypothesis is true and the conclusion is false:

Name Statement
\(\cal M1\) Cohen's original model Add a denumerable number of generic reals (subsets of \(\omega\)), \(a_1\), \(a_2\), \(\cdots\), along with the set \(b\) containing them

Code: 3

Comments:


Edit | Back