Generically extendible cardinals

Abstract

In this paper, we study the notion of a generically extendible cardinal, which is a generic version of an extendible cardinal. We prove that the generic extendibility of $\ddot{I}{‰}_1$ or $\ddot{I}{‰}_2$ has small consistency strength, but that of a cardinal $>\ddot{I}{‰}_2$ does not. We also consider some results concerned with generically extendible cardinals, such as indestructibility, generic absoluteness of the reals, and Boolean valued second order logic.