Fanxin Wu : Randomizing set theory

Posted by Fanxin Wu , part of the Louise Hay Logic Seminar.

At

Feb. 24, 2022, 4 p.m.

In

636 SEO

Abstract

A short proof of consistency of $V\neq L$ goes like this: take a random subset $A$ of $\omega$. The probability of $A=X$ for any fixed $X\subseteq\omega$ is zero, and thus $A$ is different from all $X$, so it is new, and it cannot be in $L$ by absoluteness. We explain how this "proof" is made rigorous by the Boolean algebra formulation of forcing.