Logic Seminar

Slawomir SoleckiCornell University
$\kappa$-Borel sets, $\kappa$-Baire spaces, and filtrations between topologies

Friday, September 20, 2024 - 2:55pm
Malott 230

Filtrations are certain transfinite sequences of topologies increasing in strength and interpolating between two given topologies $\sigma$ and $\tau$, with $\tau$ being stronger than $\sigma$. We prove general results on stabilization at $\tau$ of filtrations interpolating between $\sigma$ and $\tau$. These topological results involve an interplay between $\kappa$-Borel sets with respect to the topology $\sigma$ and $\kappa$-Baireness of the topology $\tau$.