News & Events

PhD Defence: Kostia Chardonnet

Towards a Curry-Howard Correspondence for Quantum Computation
by Kostia Chardonnet
Monday 9 January 2023 at 2pm
Salle des thèses, PCRI and online

Abstract: In this thesis, we are interested in the development of a Curry-Howard correspondence for quantum computing, allowing to represent quantum types and quantum control-flow. In the standard model of Quantum Computation, a classical computer is linked to a quantum coprocessor. The classical computer can then send instructions to allocate, update, or read quantum registers. The programs executed by the coprocessor are represented by a quantum circuit: a sequence of instructions that applies unitary operations to the input quantum bits. Read more...

PhD Defence: Amrita Suresh

Formal Verification of Communicating Automata
by Amrita Suresh
Monday 12 December 2022 at 2pm
Room 1Z18, ENS Paris-Saclay and online

Amrita Suresh

Abstract: Distributed systems involve processes that run independently and communicate asynchronously. While they capture a wide range of use cases and are hence, ubiquitous in our world, it is also particularly difficult to ensure their correctness.

In this thesis, we model such systems using mathematical and logical formulation, and try to verify them algorithmically. In particular, we focus on FIFO (First-In First-Out) machines, with one or more finite-state machines communicating via unbounded reliable FIFO buffers. Read more...

PhD Defence: Mathieu Hilaire

Parity games and reachability in infinite-state systems with parameters
by Mathieu Hilaire
Thursday 13 December 2022 at 9am
Room 1Z71, ENS Paris-Saclay and online

Abstract: The most standard model checking approaches are limited to verifying concrete specifications, such as “can we reach a configuration with more than 10 time units elapsing ?”. Nevertheless, for certain computer programs, like embedded systems, the constraints depend on the environment. Thus arises the need for parametric specifications, such as “can we reach a configuration with more than p time units elapsing ?” where p is a parameter which takes values in the non-negative integers.

In this thesis, we study parametric pushdown, counter and timed automata and extensions thereof. In addition to expressing concrete constraints (on the stack, on the counter or on clocks), these can employ parametric constraints. The reachability problem for a parametric automaton asks for the existence of an assignment of the parameters such that there exists an accepting run in the underlying concrete automaton. In addition to the reachability problem, we consider parametric parity games, two player games where players alternate choosing assignments for each parameters, then alternate moving a token along the configurations of the concrete automaton resulting from their choice of parameter assignment. We consider the problem of deciding which player has a winning strategy.


Portraits de chercheurs : Evelyne Contejean

Evelyne Contejean

Un article sur Evelyne Contejean vient de paraitre dans la rubrique Portraits de chercheurs des Actualités de l'Université Paris-Saclay.

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Portraits de chercheurs : Thomas Nowak

Thomas Nowak

Un article sur Thomas Nowak vient de paraitre sur le site de l'ENS Paris-Saclay.

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PhD Defence: Gabriel Hondet

Expressing Predicate Subtyping in Computational Logical Frameworks
by Gabriel Hondet
Tuesday 27 September 2022 at 5pm
ENS Paris-Saclay, Room 1Z14

Abstract: Safe programming as well as most proof systems rely on typing. The more a type system is expressive, the more these types can be used to encode invariants which are therefore verified mechanically through type checking procedures. Predicate subtyping extends simple type theory by allowing terms to be defined by predicates. A predicate subtype { x : A | P(x) } is inhabited by terms t of type A for which P(t) holds. This extension provides a rich and intuitive but undecidable type system.


Prix Doctorants STIC du plateau de Saclay pour Pierre Vandenhove

Pierre Vandenhove est lauréat d'un accessit au Prix « Doctorants » du plateau de Saclay dans la domaine STIC - Sciences et Technologies de l'Information et la Communication.


Nouveau livre : Informatique MPI


Fin août 2022, vient de sortir un nouveau livre par Thibaut Balabonski, Sylvain Conchon, Jean-Christophe Filliâtre, Kim Nguyễn, Laurent Sartre.

Il s'intitule "Informatique - MPI2/MPI - CPGE 1re et 2e années: Cours et exercices corrigés" et vise les enseignants d'informatique et les élèves des nouvelles classes préparatoires MP2I et MPI. En voici la table des matières.

En plus de son poids, il faut souligner le site lié qui fournit tous les codes et données du livre.

Philippe Schnoebelen receives LICS 2022 Test-of-Time Award

Philippe Schnoebelen

Philippe Schnoebelen receives the LICS Test-of-Time Award 2022 for the article Temporal Logic with Forgettable Past co-authored with François Laroussinie (Université Paris-Cité) and Nicolas Markey (IRISA, CNRS). At the time of the writing of the article in 2002, the three authors were members of the same laboratory LSV which integrated the LMF in 2021.

The LICS - Logic in Computer Science conference is the most prestigious annual forum on theoretical and practical topics in computer science related to logic in a broad sense. The LICS Test-of-Time Award award recognizes a small number of papers from the LICS proceedings over the past 20 years (i.e., the paper in question dates from LICS 2002 and was considered this year) that have best stood the "test of time." In selecting these papers, the award committee considers the influence they have had since their publication; due to the fundamental nature of LICS work, the impact is often not felt immediately, hence the 20-year perspective.


LICS Test-of-Time Award pour Philippe Schnoebelen

Philippe Schnoebelen

Philippe Schnoebelen reçoit le LICS Test-of-Time Award 2022 pour l'article Temporal Logic with Forgettable Past cosigné avec François Laroussinie (Université Paris-Cité) et Nicolas Markey (IRISA, CNRS). Au moment de la rédaction de l'article en 2002, les trois auteurs étaient membres du même laboratoire LSV qui a intégré le LMF en 2021.

La conférence LICS — Logic in Computer Science est le plus prestigieux forum annuel sur des sujets théoriques et pratiques en informatique liés à la logique au sens large. Le prix LICS Test-of-Time Award récompense un petit nombre d'articles tirés des actes du LICS des 20 dernières années (c'est-à-dire que l'article en question date du LICS 2002 et a été pris en considération cette année) qui ont le mieux résisté à "l'épreuve du temps”. En sélectionnant ces articles, le comité d'attribution tient compte de l'influence qu'ils ont eue depuis leur publication ; en raison de la nature fondamentale des travaux de la LICS, l'impact n'est souvent pas ressenti immédiatement, d'où la perspective de 20 ans.