Proceedings of 21st IEEE Symp. on Logic in Computer Science, LICS 2006, pp. 37-46. Abstract
Small substructures and decidability issues
for first-order logic with two variables
, with E. Kieronski.
Preprint of journal version of LICS'05 paper, revised 2011, 41 pages.
Abstract
Modal and guarded characterisation theorems over finite
transition systems,
Annals of Pure and Applied Logic, volume 130, 2004, pp. 173-205.
Abstract
Elementary proof of the van Benthem - Rosen characterisation theorem,
technical report,
TUD online preprint no.2342, 2004, 11 pages.
Abstract
Bisimulation invariance and finite structures,
Lecture Notes in Logic, Logic Colloquium 02, 2006, pp. 276-298.
Abstract
Finite conformal hypergraph covers and
Gaifman cliques in finite structures,
with I. Hodkinson.
Bulletin of Symbolic Logic, volume 9, 2003, pp. 387-405.
Abstract
Back and forth between guarded and modal logics,
with E. Grädel and C. Hirsch.
ACM Transactions on Computational Logic,
volume 3, 2002, pp. 418-463.
Abstract
Two Variable First-Order Logic over Ordered Domains.
Journal of Symbolic Logic, volume 66, 2001, pp. 685-702.
Abstract
Epsilon-Logic is More Expressive Than First-Order Logic
over Finite Structures.
Journal of Symbolic Logic, volume 65, 2000, pp. 1749-1757.
Abstract
An Interpolation Theorem.
Bulletin of Symbolic Logic, volume 6, 2000, pp. 447-462.
Abstract
On Logics with Two Variables, with E. Grädel.
Theoretical Computer Science, 224, 1999, pp. 73-113.
Abstract
Bisimulation-Invariant Ptime and Higher-Dimensional mu-Calculus.
Theoretical Computer Science, 224, 1999, pp. 237-266.
Abstract
Beth
Definability for the Guarded Fragment,
with E. Hoogland and M. Marx.
LPAR'99, LNAI, vol. 1705, Springer 1999, pp. 273-285.
Abstract
Also in: JFAK,
Essays Dedicated to Johan van
Benthem on the Occasion of his 50th Birthday.
Eliminating Recursion in the mu-Calculus.
in Proceedings of STACS'99, LNCS 1563, Springer 1999, pp. 531-540.
Abstract
On the Boundedness Problem for Two-Variable First-Order Logic,
with P. Kolaitis.
LICS'98.
Abstract
Undecidability Results on Two-Variable Logics,
with E. Grädel and E. Rosen.
Archive for Mathematical Logic, 38, 1999, pp. 313-345.
Abstract
Selected Talks:
See also (fuller) list of talks
Controlling Cycles in Finite Hypergraphs
Monday Lecture: Methods for Discrete Structures,
Berlin 2011.
The Freedoms of Guarded Bisimulation
Invited talk,
Computer Science Logic ,
Bergen 2011.
Tractable Finite Models
Invited talk,
Logic Colloquium, Barcelona 2011.
Expressive Completeness
Invited talk,
Advances in Modal Logic 2010, Moscow 2010.
Highly Acyclic Groups, Hypergraph Covers and GF
LICS 2010, Edinburgh 2010.
Diagonalen, die den Rahmen sprengen
Begleitprogramm zur hessischen Mathe-Olympiade 2010, TU Darmstadt 2010.
Methods For Deciding Boundedness of Least Fixed Points
Fachgruppentreffen Logik in der Informatik, Frankfurt 2009;
and (edited) Computer Laboratory, Oxford 2009.
Bisimulation Invariance over Transitive Frames
IMCS workshop on Logic and Algorithms, Edinburgh, July 2008.
Games and Fragments of
FO over Special Classes of (Finite) Structures
mini-course at
MATHLOGAPS summer school, Aussois, France, June 2007.
Boundedness in Universal First-Order Logic
LICS 2006, Seattle.
Model Theoretic Methods for Special Classes
of (Finite) Structures
4 lecture tutorial,
Newton Institute Programme on Logic and Algorithms 2006,
Workshop on Finite and Algorithmic Model Theory
, Durham, 2006.
Logik und Spiele
Mathematisches Kolloquium TU Darmstadt,
February 2004 (in German).
Bisimulation Invariance and Instances of Expressive Completeness
Invited talk,
12th International Congress of Logic,
Methodology and Philosophy of Science, LMPS, Oviedo, 2003.
Extensions of Partial Automorphisms;
Hypergraphs and Guarded Logics
Invited talk,
Euresco Conference
on
Symmetries, Ordered Structures, Model Theory and
Combinatorics, Hattingen, 2003.
Invariances, Games, Models,
and (Finite) Model Theory in Tractable Fragments of FO
Invited talk,
Colloquium Logicum, Muenster, August 02
(in conjunction with the ASL European Summer Meeting).
For earlier versions presented at Darmstadt and Leeds (December 01),
Edinburgh and London (May 02), and Amsterdam (June 02) see edited slides
Bisimulation, Unravellings, and Covers.
Logics - Invariances - Games :
domain specific algorithmic model theory
Survey talk, held at the University of Edinburgh, April 01.
photographs by U. Berger, 2001
and by H. Otto, 2009
