In Zermelo-Fraenkel set theory without the axiom of choice a strong partition cardinal is an uncountable well-ordered cardinal such that every partition of the set of size subsets of into less than pieces has a homogeneous set of size .
The existence of strong partition cardinals contradicts the axiom of choice. The Axiom of determinacy implies that ℵ1 is a strong partition cardinal.
Famous quotes containing the words strong and/or cardinal:
“When the ivy has found its tower, when the delicate creeper has found its strong wall, we know how the parasite plants grow and prosper.”
—Anthony Trollope (1815–1882)
“What people don’t realize is that intimacy has its conventions as well as ordinary social intercourse. There are three cardinal rules—don’t take somebody else’s boyfriend unless you’ve been specifically invited to do so, don’t take a drink without being asked, and keep a scrupulous accounting in financial matters.”
—W.H. (Wystan Hugh)