Berkeley Cardinals and Vopenka's Principle
Abstract
We introduce "n-choiceless" supercompact and extendible cardinals in Zermelo-Fraenkel set theory without the Axiom of Choice. We prove relations between these cardinals and Vopenka's Principle similar to those of Bagaria's work in his papers "C(n)-Cardinals" and "More on the Preservation of Large Cardinals Under Class Forcing." We use these relations to characterize Berkeley cardinals in terms of a restricted form of Vopenka's Principle. Finally, we establish the equiconsistency of the "n-choiceless" extendible cardinals with their original counterparts, and study the consistency strength of other relevant theories.
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