NERDS: New England Recursion & Definability SeminarSunday, November 6, 20162:50 pmScience Center, Room E104, Wellesley College, Wellesley, MA

# Comparing notions of effective genericity

## Rose Weisshaar

### Notre Dame University

In recent work, Cholak, Dzhafarov, Hirst and Slaman showed that for *n ≥ 3*, every Mathias *n*-generic computes a Cohen *n*-generic. It is natural to wonder how other types of generic objects compare to one another. We consider generics for an effective version of Hechler forcing. Adapting a method developed by Cholak, Dzhafarov, and Soskova, we show that for *n ≥ 3*, every Mathias *n*-generic computes a Hechler *n*-generic, and every Hechler *n*-generic computes a Mathias *n*-generic. Finally, we explore the (open) question of whether, for *n ≥ 3*, the Mathias *n*-generics and the Hechler *n*-generics occupy exactly the same Turing degrees.

Rose Weisshaar is a doctoral student at Notre Dame University, under the supervision of Peter Cholak.

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on October 12th, 2016