Sylvain Schmitz
Assistant professor
Get paper from arXiv
I've been busy these last few years trying to get a clear
picture of the complexity of problems that arise from the use of
wellquasiorders and wellstructured transition systems. Here
is some of the material I coauthored on the subject:
Research
 Keywords
 Verification, infinite systems, well quasi orders, formal languages, parsing, computational linguistics
• 
J. GoubaultLarrecq and S. Schmitz. Deciding Piecewise Testable Separability for Regular Tree Languages. In ICALP'16, Leibniz International Proceedings in Informatics 55, pages 97:197:15. LeibnizZentrum für Informatik, July 2016. ( Web page  BibTeX )

• 
R. Lazić and S. Schmitz. The Complexity of Coverability in νPetri Nets. In LICS'16, pages 467476. ACM Press, July 2016. ( Web page  BibTeX )

• 
D. Baelde, S. Lunel and S. Schmitz. A Sequent Calculus for a Modal Logic on Finite Data Trees. In CSL'16, Leibniz International Proceedings in Informatics 62, pages 32:132:16. LeibnizZentrum für Informatik, September 2016. ( Web page  BibTeX )

• 
P. Chambart, A. Finkel and S. Schmitz. Forward Analysis and Model Checking for Trace Bounded WSTS. Theoretical Computer Science 637, pages 129, July 2016. ( Web page  BibTeX )

• 
S. Schmitz. Complexity Hierarchies Beyond Elementary. ACM Transactions on Computation Theory 8(1:3), February 2016. ( Web page  BibTeX )

Full BibTeX
More publications...
 Verification Seminar, 11am, November 2nd, 2016, Department of Computer Science, Oxford University, Oxford, UK
 I presented the paper The Complexity of Coverability in νPetri Nets written with R. Lazić. Here are the slides.
 Verification Seminar, 11am, October 24th, 2016, IRIF, Paris, France
 I presented the applications of ideals of wellquasiorders for the verification of vector addition systems, based on the papers Demystifying Reachability in Vector Addition Systems and Ideal Decompositions for Vector Addition Systems with J. Leroux. Here are the slides.
 Highlights 2016, 14:51pm, September 8th, 2016, Université libre de Bruxelles, Brussels, Belgium.
 I presented a joint work with R. Lazić on the complexity of coverability in νPetri nets, an extension of Petri nets with data management and creation capabilities. Here are the papaer and the slides.
 ICALP 2016, 11:45am, July 12th, 2016, Sapienza University, Rome, Italy.
 I presented the paper Deciding Piecewise Testable Separability for Regular Tree Languages written with J. GoubaultLarrecq. Here are the slides.
 LICS 2016, 16:11pm, July 6th, 2016, Columbia University, New York, USA.
 I presented the joint paper with R. Lazić on the complexity of coverability in νPetri nets, an extension of Petri nets with data management and creation capabilities. Here are the preprint and the slides.
 Séminaire de l'équipe Méthodes Formelles, 11am, March 8th, 2016, LaBRI, Bordeaux.
 I presented a joint work with R. Lazić on the complexity of coverability in νPetri nets, an extension of Petri nets with data management and creation capabilities. Here are the preprint and the slides.
 Dagstuhl Seminar 16031 Well QuasiOrders in Computer Science, 4:30pm, January 21st, 2016, Schloss Dagstuhl, Germany.
 Wellquasiorders provide termination or finiteness arguments for many
algorithms, and miniaturised versions can furthermore be employed to
prove complexity upper bounds for those algorithms. We have however
an issue with these bounds: they go way beyond the familiar complexity
classes used in complexity theory. I discussed a definition of
complexity classes suitable for the task. In particular, unlike the
subrecursive classes they are based on, those classes support the
usual notions of reduction and completeness. The talk was based on the article Complexity hierarchies beyond Elementary.
 Reading Group on Logic, Automata, Algebra and Games, 10:30am, January 7th, 2016, Université ParisDiderot.
 Chalk talk on ideals in VAS reachability. The decidability of the reachability problem for vector addition systems is a notoriously difficult result. First shown by Mayr in 1981 after a decade of unsuccessful attempts and partial results, its proof has been simplified and refined several times, by Kosaraju and Lambert, and reproven by very different techniques by Leroux in 2011. The principles behind the original proof remained however obscure.
In this seminar, I presented the ideas behind the algorithms of Mayr, Kosaraju, and Lambert (the KLM algorithm) in the light of ideals of wellquasiorders. The interest here is that ideals provide a semantics to the structures manipulated in the KLM algorithm, bringing some new understanding to its proof of correctness. This approach is based on a joint work with Jérôme Leroux (LaBRI) presented at LICS'15.
More talks...
Other activities
 Steering committee of GTVerif.
 PC member for conferences Petri nets'17, STACS'17, and workshops RP'15, RP'12, CSLP'12, LDTA'12, LDTA'11, TAG+10, TAG+9;
 organizing committees of Highlights 2014 (cochair), GTVérif 2014, GTVérif 2013 (cochair), CIAA'05.