Moritz Müller FWF
# FWF Project P 28699

# Complexity theory in feasible mathematics

The project is hosted at Vienna universities Kurt Gödel Research Center for Mathematical Logic (KGRC)
directed by Sy David Friedman.

General information about the project can be found here.

### Team at the KGRC

Moritz Müller is funded as the project leader.

Jan Pich holds a funded postdoctoral position.

Jan Bydzovsky is working on a master thesis on a topic related to the project.

### International collaborators

Albert Atserias at Universitat Polytecnica de Catalunya, Barcelona, Spain.

Yijia Chen at Fudan University, Shanghai, China.

Jan Krajicek at Charles University, Prague, Czech Republic.

### Visitors

Igor Oliveira visits the KRGC from 2017-01-16 to 2017-01-21.

Michal Garlik visits the KRGC from 2017-01-23 to 2017-01-27 and gives a talk.

Yijia Chen visits the KRGC from 2017-08-12 to 2017-08-19 and gives a talk.

Hubie Chen visits the KRGC from 2017-11-30 to 2017-12-10 and gives a talk.

### Talks

On the relative strength of finitary combinatory principles By M. Müller, KGRC Forschungsseminar, Vienna, 2017-12-14.

Proof complexity By M. Müller, Algebra Seminar, TU Vienna, 2017-12-01.

Provability of weak circuit lower bounds By J. Pich, Prague bounded arithmetic
workshop, Prague, 2017-11-2.

Provability of weak circuit lower bounds
By J. Pich, Royal Holloway, University of London, 2017-10-10.

Cobham recursive set functions By M. Müller, Barcelona Set Theory Seminar, Universitat de Barcelona, 2017-03-16.

Gentzen and Frege systems for QBF By J. Pich, Computational Logic Day, KGRC, Vienna, 2017-01-13.

Complexity theory in feasible mathematics. By J. Pich, KGRC Forschungsseminar, Vienna, 2016-10-03.

### Publications

Feasibly constructive proofs of succinct weak circuit lower bounds. By J. Pich and M. Müller.

*Preprint* Electronic Colloqium on Computational Complexity
ECCC TR17-144.

*Submitted October 2017*.

Pseudo proof systems and hard instances of SAT. By J. Maly and M. Müller.

*Submitted March 2017*.

The parameterized space complexity of model-checking bounded variable first-order logic. By Y. Chen, M. Elberfeld and M. Müller.

*Submitted March 2017*.

Reasons for hardness in QBF. By O. Beyersdorff, L. Hinde and J. Pich.

Proceedings of the 37th IARCS Annual Conference on Foundations of Software Technology and Theoretical
Computer Science, to appear, 2017.

Subset-bounded recursion and a circuit model for Cobham recursive set functions. By A. Beckmann, S. Buss, S.-D. Friedman, M. MÃ¼ller, N. Thapen.

*Submitted December 2016*.