HOD dichotomy: Difference between revisions

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* There is a regular cardinal \(\gamma > \delta\) which is not \(\omega\)-strongly measurable in HOD.
* There is a regular cardinal \(\gamma > \delta\) which is not \(\omega\)-strongly measurable in HOD.


Then we have a strong dichotomy: if \(\delta\) is an [[extendible]] cardinal, either:
Then we have a strong dichotomy: if \(\delta\) is an extendible cardinal, either:


* Every [[Cofinality|regular]] cardinal greater than \(\delta\) is \(\omega\)-strongly measurable in HOD.
* Every [[Cofinality|regular]] cardinal greater than \(\delta\) is \(\omega\)-strongly measurable in HOD.
* No [[Cofinality|regular]] cardinal greater than \(\delta\) is \(\omega\)-strongly measurable in HOD.
* No [[Cofinality|regular]] cardinal greater than \(\delta\) is \(\omega\)-strongly measurable in HOD.


None of these three statements are particularly hard to prove. The HOD hypothesis says that there is a proper class of cardinals \(\lambda\) which are not \(\omega\)-strongly measurable in HOD: therefore, if there is an extendible cardinal and the HOD hypothesis holds, then \(\mathrm{HOD}\) is close to \(V\).
Neither of these three statements are particularly hard to prove.