One Repeat Point Gives a Closed, Unbounded Ultrafilter on {\omega_1}

Abstract

It is shown that the consistency strength of ZF + DC + "the closed unbounded ultrafilter on omega_1 is an ultrafilter" is exactly ZFC + one measurable cardinal.Comment: I apologize for the fact that this is not ready for publication. I've gone back to revise it several times, and each time got distracted by something new. I've decided that it is better to at least make it available in its current for