All Questions

Every real number is $Δ^1_2$ in some $ω$-model of ZFC\P. I am looking for analogous statements for $Δ^1_3$ definability and transitive models, where the situation is more subtle. What is the ...

My question is about two types of consequence of large cardinals, considered over ZFC on their own. First, we have statements of the form, "The club filter on $\omega_1$ is an ultrafilter when ...

I am asking for a reference request/proof sketch for the result of Steel that characterizes $L[T_{2n+1}]$ as a direct limit of mice. Given that both $L[T_{2n+1}]$ and $M_{2n}$ have a $\Sigma_{2n+2}$ ...

With the current research, it seems that we are in a position to get extremely powerful absoluteness theorems (like $\Sigma^2_0$-absoluteness, $\Sigma^2_1$-absoluteness, $\Sigma^2_2$, $\diamondsuit_G$,...

In his talk A Condensed History of Condensation, Welch presents the following recursive sharp function, that is total when all sharps exist: \begin{align*} \# \colon ON &\to \mathcal{P}(ON) \\ \...

In the course of a (fun but silly) project I'm working on, I've run into the following class of determinacy notions: Suppose I have a "reasonably definable" class $\mathcal{C}$ of games (in the usual ...