# A Proof-Theoretic Approach to Slow Consistency

**Date**: Wednesday 29 March 2017, 14:00 – 15:30**Location**: Mathematics Level 8, MALL 1 & 2, School of Mathematics**Type**: Proofs, Constructions and Computations, Seminars, Pure Mathematics**Cost**: Free

#### Anton Freund, University of Leeds. Part of the proofs, constructions and computations seminar series.

The slow consistency statement for Peano Arithmetic, due to S.-D. Friedman, Rathjen and Weiermann, is strictly weaker than the usual consistency statement (but still unprovable in Peano Arithmetic). So far, all proofs of this fact use model-theoretic results of Solovay or Sommer. I will present a new argument that relies on proof-theoretic methods, thus extending the toolbox for further applications.

**Anton Freund, ***University of Leeds*