polski

Szczepan Hummel, PhD

University of Warsaw
Faculty of Mathematics Informatics and Mechanics
Institute of Informatics


e-mail: shummel@mimuw.edu.pl

Scientific CV

Scientific Interests:

Automata theory, formal languages, infinite games, set theory, topology, verification.


PhD Thesis:

Topological Complexity of Sets Defined by Automata and Formulas (supervisor: Damian Niwiński, reviewers: Emanuel Kieroński, Igor Walukiewicz), University of Warsaw 2017
 → slides from the talk given at public PhD defence
 → Extended Summary of PhD Dissertation


Publications (dblp):

On Unambiguous Regular Tree Languages of Index (0,2) (co-authors: Jacques Duparc and Kevin Fournier), CSL 2015 (Berlin)

Unambiguous Tree Languages Are Topologically Harder Than Deterministic Ones, GandALF 2012 (Naples)
 → slides from the talk (given also at GAMES 2012 workshop in Naples)

The Topological Complexity of MSO+U and Related Automata Models (co-author: Michał Skrzypczak), Fundamenta Informaticae, 119(1) 2012
 → slides from the talk given by Michał Skrzypczak at GAMES 2011 (Paris)
Former conference version containing weaker result:
On the Topological Complexity of MSO+U and Related Automata Models (co-authors: Michał Skrzypczak and Szymon Toruńczyk), MFCS 2010 (Brno)
 → slides from the talk
 → slides from the talk given at GAMES 2010 (Oxford)

On The Borel Inseparability of Game Tree Languages (co-authors: Henryk Michalewski and Damian Niwiński), STACS 2009 (Freiburg)
 → slides from the talk
 → slides from the talk given at GAMES 2008 (Warsaw)


Other texts and talks:

Unambiguity-Preserving Operation on Tree Languages That Lifts Topological Complexity, Highlights 2013 (Paris)

Hierarchies for languages of infinite trees — table summarizing state of the art for hierarchies (Borel, Wadge, Rabin-Mostowski index, etc.) for languages of infinite trees (strictness, height, decidability) (2007)

Separation Properties of Tree Languages Definable by Automata (Polish)master's thesis in mathematics writen under supervision of Damian Niwiński and with support of Henryk Michalewski (2008)

Characteristics of Borel pointclasses (Polish) — talk given at students seminar on Topology and Set Theory (2007)

Comparing Sizes of Representations of Regular Languages of Unranked Trees (Polish)master's thesis in computer science writen under supervision of Mikołaj Bojańczyk (2006)

Decidability of Unknotting Problem (Polish)bachelor's thesis in mathematics (2005)

Minimization of nondeterministic automata on finite and infinite words (Polish) — talk given on students seminar on Logic, Computational Theory and Cryptography (2005)


Teaching:

Summer Semester 2011/2012:

Languages, automata and computations (Polish), class

Available for students: Tuesday 13:45–15:15

Summer Semester 2010/2011:

Languages, automata and computations (Polish), class

Summer Semester 2008/2009:

Individual Programming Project (Polish), lab

Winter Semester 2008/2009:

Languages, automata and computations (Polish), class

Winter Semester 2007/2008:

Languages, automata and computations (Polish), class

Introduction to Computer Science (Polish), class/lab