Wikipedia / Supercompact cardinal
Wikipedia / Supercompact cardinal
In set theory, a supercompact cardinal is a type of large cardinal independently introduced by Solovay and Reinhardt. They display a variety of reflection properties.
Formal definition
is any ordinal is -supercompact means that there exists an elementary embedding into a transitive inner model with critical point and
is supercompact.
is supercompact there exists a normal measure, in the following sense.
is defined as follows:
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An ultrafilter is fine.
Properties
Supercompact cardinals have reflection properties. If a cardinal with some property (say a 3-huge cardinal is supercompact and the generalized continuum hypothesis.
Finding a canonical inner model for supercompact cardinals is one of the major problems of inner model theory.
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Supercompactness has a combinatorial characterization similar to the property of being ineffable is stationary (in \(P_\kappa(A)\)).
Magidor obtained a variant of the tree property which holds for an inaccessible cardinal if it is supercompact.