Mathematical logic seminar - Apr 30 2019

Time: 3:30pm - 4:30 pm

Room: Wean Hall 8220

Speaker:     Shaun Allison    
CMU

Title: Generic preturbulence and forcing

Abstract:

We revisit the topological property of some Polish group actions known as preturbulence, this time giving a formulation of it using forcing. We will show that this definition, due to Jindrich Zapletal, is equivalent to the others, and give another proof of Hjorth's turbulence theorem. Time permitting, we will discuss some dichotomy results relating to turbulence and classification by countable structures.