Graph explorer

Potential Wadge classes

Let $\bfΓ$ be a Borel class, or a Wadge class of Borel sets, and $2\leq d\leqω$ a cardinal. We study the Borel subsets of ${\mathbb R}^d$ that can be made $\bfΓ$ by refining the Polish topology on the real line. These sets are called potentially $\bfΓ$. We give a test to recognize potentially $\bfΓ$ sets.