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