Cohen \(\cal M28\): Morris' Model II | Back to this models page

Description: Morris constructs a generic extension of acountable standard model of ZFC in which there is a proper class ofgeneric sets

When the book was first being written, only the following form classes were known to be true in this model:

Form Howard-Rubin Number Statement
0  \(0 = 0\).

When the book was first being written, only the following form classes were known to be false in this model:

Form Howard-Rubin Number Statement
91

\(PW\):  The power set of a well ordered set can be well ordered.

209

There is an ordinal \(\alpha\) such that for all \(X\), if \(X\) is a denumerable union of denumerable sets then \({\cal P}(X)\) cannot be partitioned into \(\aleph_{\alpha}\) non-empty sets.

Historical background: ( The generic sets are added at each level \(R_{\alpha} =\{x: \hbox{ rank of \)x\( is } < \alpha\}\).) In this model, for each ordinal\(\alpha\), there is a set \(X\) such that \(X\) is a denumerable union ofdenumerable sets and \(\cal P(X)\) can be partioned into \(\aleph_{\alpha}\)nonempty sets.

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