Mihaela Sighireanu (IRIF) is organizing the second edition of SL-COMP, a competition of solvers for separation logic. The final results will be presented at ADSL 2018, a workshop of FLOC2018, which will take place in Oxford on the 13.07.18.
separation logic

Separation logic is a language for describing properties and reasoning about programs that use mutable data structures (i.e. memory cells and pointers). Separation logic has a special support for local reasoning, which is the ability to use and compose properties that involve a subset of the data configuration only: it separates the relevant portion of the data structure from the irrelevant one. Local reasoning gives more compact proofs and specifications for imperative programs than with prior formalisms. Furthermore, it helps with the scalability of proofs done in automatic and semi-automatic verification and program analysis tools.

Mihaela Sighireanu (IRIF) is co-chair of the 18th International Workshop on Automated Verification of Critical Systems (AVOCS) which will take place in Oxford from 18.07.18 to 19.07.18 as part of FLOC2018.


Raphaëlle Crubillé (PhD student IRIF) will present at LICS 2018 an analytic account of the discrete probabilities fragment of a denotational model for higher-order programming with general probabilities, hopefully a first step towards proving that this model is fully abstract.
fully abstract

The quest for a fully abstract model for the contextual equivalence of PCF, a paradigmatic functional language, has been influential in the area of programming languages semantics. A model is fully abstract if it is both sound and complete. A denotational model is complete for a given notion of equivalence between programs if equivalent programs have the same denotation, some mathematical object they are mapped to; it is sound if programs having the same denotation are equivalent.

Berenice Delcroix-Oger (IRIF) participated to the annual festival "Salon Culture & Jeux Mathématiques 2018". On the following video (1:50), she presents a funny game where mathematics help you perform magic tricks!

Amina Doumane

Amina Doumane (former PhD student at IRIF, now at LIP) was awarded the Ackermann prize of EACSL for her PhD thesis entitled On the infinitary proof theory of logics with fixed points.

TYPES 06.06.2018
Delia Kesner (IRIF) and Matthieu Sozeau (IRIF) will both give invited talks entitled “Multi Types for Higher-Order languages” and “The Predicative, Polymorphic Calculus of Cumulative Inductive Constructions and its implementation” at TYPES 2018, held in Braga (Portugal), June 18-21.

IRIF distinguished talk 06.06.2018
We are delighted to host as part of our IRIF Distinguished Talks Series Christos Papadimitriou (Columbia University) on July 13, 10:30 for a talk entitled “A computer scientist thinks about the Brain”.

Software Heritage

Today Roberto Di Cosmo (professor at IRIF) with a ceremony at UNESCO opened to the public the archives of Softwareheritage.org, a worldwide initiative to create a universal library of computer programme source codes since the dawn of the digital age. .


Amos Korman (IRIF) Amos Korman is co-chairing, and organizing the 6th Workshop on Biological Distributed Algorithms, to be held in London in July, the 23rd.
biological algorithm

Biological algorithm is a term used to describe the biological processes from an algorithmic, or computer scientific, perspective. It concerns questions such as what are the algorithmic challenges faced by the biological organism, and what are the algorithmic principals used in order to overcome these challenges. For example, when a group of ants finds a large piece of food and needs to decide its navigation rout back to the nest, what are the benefits and pitfalls of noise in their communication?

Peter Habermehl (IRIF) and Benedikt Bollig (LSV, ENS Paris-Saclay) organize the research school MOVEP (Modelling and Verification of Parallel Processes), from on July 16-20 in Cachan.

Collège de France

Claire Mathieu (IRIF associate member) organizes a 1-day colloquium on Approximation algorithms and networks at Collège de France on June 7. This is part of the Chair in Informatics and Computational Sciences at College de France in association with INRIA.
approximation algorithm

The approximation algorithms are algorithms that produce a solution that approximates the best possible solution of an optimization problem. While finding the optimal solution of practical problems is often infeasible, an approximation algorithm usually produces its solution in an efficient way and provides formal guarantees about the quality of the approximation. An example of such a problem is the so-called “traveling salesman problem” which consists in finding among all possible itineraries the shortest route that allows a salesman to visit a given set of cities and come back home.
Informatique & sciences du numérique

« Tous femmes de numérique ! » Après leur rencontre avec 4 informaticiennes de l’IRIF, 14 lycéennes du Lycée Jules Ferry ont expliqué à leurs camarades l’exposition permanente du Palais de la découverte sur l’informatique et les sciences du numérique le 29/05.


Marie Kerjean (PhD student IRIF) will present at LICS 2018 a logical account for linear partial differential equations. With this work, she unveils a bridge between mathematical physics and proof theory, paving the way for exciting and mutually beneficial transfers of techniques.

A sequent represents a theorem by a sequence of hypotheses and the sequence of possible theses they imply. This formalism underlines a symmetry hypotheses/theses ruled by negation and is used in sequent calculus to formalise proofs and to study their properties.

Pierre Vial (IRIF) will present at LICS 2018 an excerpt of his PhD work at IRIF proving that every lambda-term has an infinite linear representation in the infinitary relational model. This work pioneers a technique that allows giving a semantic even to unproductive programs.

A part of a program is unproductive if it performs an infinite number of computing steps without any interaction with the rest of the program or external devices. Unproductive code is basically useless, and may even be unsafe, and detecting parts of code that are unproductive is important to improve software quality.

Paul-André Melliès (IRIF) will present at LICS 2018 his work on ribbon tensorial logic, a primary logic designed to reveal the secret topology of reasoning. This is the first time that logical proofs are faithfully translated into topological tangles using functorial knot theory.
knot theory

Knot theory studies mathematical knots. These are like the usual shoelaces and rope knots but with the difference that the ends of the string are joined together so that it cannot be undone. Of particular interest is the study of when two knots are equivalent, that is when one can be transformed into the other without cutting the string or passing the string through itself. The theory has applications in physics, biology, chemistry, and computer science. For instance, the security of some quantum money relies on the assumption that given two different looking but equivalent knots, it is difficult to explicitly find a transformation that takes one to the other.
Institut de France

Miklos Santha (IRIF) participates to the conference-debate Calcul, communication, simulation et métrologie quantiques : des principes aux réalisations concrètes organized by Académie des sciences at the Institut de France on May 15.


IRIF is proud to announce that Delia Kesner, professor of University Paris Diderot and researcher at IRIF, was appointed senior member of IUF.


Six papers coauthored by IRIF members will be presented at the prestigious conference LICS'18 in Oxford this summer. Topics range from λ-calculus, to Separation Logic…


Victor Lanvin (PhD student of Giuseppe Castagna, IRIF) is awarded the Google PhD fellowship! Through the FSMP, Google will give a significant support to Victor's research work on gradual typing.
gradual typing

Gradual typing is a technique that allows the programmer to control which parts of a program check their type correctness (i.e., that apples are added to apples) before execution and which parts check it during their execution instead. It is often used to gradually add the before-execution check to dynamic languages, like JavaScript, which perform the check only at run-time, since it is generally better to find errors before the execution of a program rather than during its execution.
Numeration 2018

The conference Numeration 2018 will be held on May 22-25 at the Univerity Paris Diderot, and is organized by Valérie Berthé, Christiane Frougny and Wolfgang Steiner from IRIF.


“The Kappa platform for rule-based modeling”, a collaboration between Jean Krivine (IRIF) and researchers from Harvard University, ENS and Santa Cruz University will be presented at ISMB2018.


The next meeting of the ANR project DESCARTES, aiming at defining a modular approach for distributed computing, will take place at IRIF on March 28, 2018. Scientific talks are public.

Delta project logo

The next meeting of the ANR project DELTA, conducting research about the new challenges in Logic, Automata and Transducers, will take place at University Paris Diderot from 2018/03/26 to 2018/03/28. Scientific talks are public.

An automaton is a construct made of states designed to determine if a sequence of inputs should be accepted or rejected. It starts from initial state and when it receives a new input it moves to another state according to the way it was programmed. If at the end of all inputs the automaton is in a state designated as final, then the sequence of inputs is accepted, otherwise it is rejected.

IRIF distinguished talk 08.03.2018
In the scope of the IRIF Distinguished Talks Series Monika Henzinger (University of Vienna) will give on April 13 a talk on “The state of the art in dynamic graph algorithms”.

Algorithm: an algorithm is the formal description of a procedure that is used to solve a class of problems. The description consists in a sequence (of finite length) of operations that are interpreted unambiguously by who/what is executing the algorithm. Every algorithm can be directly executed or simulated by any Turing-complete system.

Adrian Kosowski (IRIF), together with Bartek Dudek (University of Wroclaw), will present at STOC 2018 a new protocol for spreading information in a population. This is the first time that methods of oscillatory dynamics are used to solve a basic task of information dissemination.
information dissemination

Information dissemination is the process by which a piece of information is propagated in a distributed system through direct communications from node to node. Rumor spreading between humans or broadcasting in a network are two typical examples. Information propagation is a basic building block of many distributed algorithms and its analysis is often critical in understanding their complexity.

Constantin Enea (IRIF) is an organizer of the 2018 edition of the EPIT research school, on the subject of software verification, to he held in Aussois on May 7-11 2018.


FSMP offers 20 PhD student positions in Maths and TCS under H2020 COFUND project MathInParis. As a member of the FSMP network, IRIF is an eligible hosting lab. Call for application is open until April, 1st 2018. Applicants must be international students, but master students already in France for less than a year are eligible.

Paris Diderot

Université Paris Diderot has opened three permanent positions in Computer Science (1 professor on Graph and applications, 1 assistant professor on Software Science, 1 assistant professor on Data Science). Recruited researchers will join IRIF.

Palais de la découverte

Laurent Viennot (IRIF, Inria) is Scientific Curator of the exhibition Informatique et sciences du numérique, at Palais de la découverte, starting March 13, 2018.

Amina Doumane

Amina Doumane, now at LIP, was awarded the “La Recherche” prize in the Computer Science category for her paper entitled Constructive Completeness for the linear-time mu-calculus, a work accomplished during her PhD at IRIF and that appeared in the proceedings of LICS’17.


The first on-the-fly quantum money transaction was implemented by researchers in Paris, including Iordanis Kerenidis. ​Quantum ​money is provably unforgeable​ due to the no-cloning property of quantum information.​
quantum information

Quantum Information is the information stored in a quantum system. A quantum system is composed of one or many qubits: the fundamental unit of quantum information. A qubit is a 2-dimensional vector. The basis encodes two classical values of a bit. Quantum information, i.e. Von Neuman entropy, is the analogous of Shannon entropy for classical information, and it is often used to measure physical properties of a quantum system, like the entanglement.

The international French and Argentina CNRS laboratory called INFINIS lead by Delia Kesner (IRIF) and Sergio Yovine (CONICET) is presented in the CNRS Rio newsletter.

Maurice Nivat

IRIF organizes on February, 6th a Scientific Day in memory of Maurice Nivat, professor at Paris Diderot University and a pionneer of theoretical computer science. Please register.


Lucas Boczkowski and Amos Korman from IRIF, with their co-authors, will present at ITCS 2018 a non-conditional lower bound on information dissemination in stochastic populations. The paper is the first ever to combine an algorithmic lower bound with a biology experiment in collective behavior.

Agence Nationale de la Recherche

January the 10th 2018, this is the kick-off meeting of the ANR project FREDDA (FoRmal mEthods for the Design of Distributed Algorithms).


IRIF and ATOS have started the first Industrial PhD Thesis (CIFRE) on quantum algorithms in France. The PhD candidate Alessandro Luongo is co-advised by Iordanis Kerenidis and Frédéric Magniez.

Amina Doumane

Amina Doumane was awarded the Gilles Kahn prize for her PhD thesis entitled « On the infinitary proof theory of logics with fixed points » supervised by Alexis Saurin, David Baelde and Pierre-Louis Curien.

Wenjie Fang

Wenjie Fang was awarded the Honorable Mention of the Gilles Kahn prize for his PhD thesis entitled « Aspects énumératifs et bijectifs des cartes combinatoires : généralisation, unification et application » and supervised by Guillaume Chapuy and Mireille Bousquet-Mélou.

Maurice Nivat

Scientific Day in memory of Maurice Nivat, professor at Paris Diderot University and a pionneer of theoretical computer science in France and in the world, who passed away on September the 21st, 2017.

6th French-Israeli Workshop on Foundations of Computer Science on November 22-23, 2017 at Tel-Aviv University, Israel.


IRIF is happy to host and organize the 59th IEEE Symposium on Foundations of Computer Science (FOCS 2018), at Maison de la Chimie, Paris, October 07-09, 2018.

2-day workshop on December 7-8: Closing workshop of ANR project on Restricted Data Access Models and 1st IRIF-IQC Workshop on Quantum Information Processing (CNRS bilateral collaboration).

Newcomers Day on November 6, 2017 at Amphi Turing

Back-to-work day of the "Proofs, programs and systems" pole on October 12-13, 2017 at room 3052.


Guillaume Lagarde and Sylvain Perifel have solved a 20-year old conjecture related to Lempel-Ziv. This will be presented at the 29th ACM-SIAM Symposium on Discrete Algorithms (SODA 2018).

IRIF has the great pleasure to welcome a new assistant professor: Bérénice Delcroix-Oger, an expert in combinatorics and computational algebra.

Closing workshop of ANR project MealyM on July 10-13, 2017 at Amphi Turing.

Victor Lanvin is awarded the first prize for the ACM Student Research Competition Grand Finals, undergraduate category. The prize will be presented on June the 24th at the Turing Award Cerimony in San Francisco.

The 5-year ERC project CombiTop of Guillaume Chapuy has started on March 1st, 2017. The purpose of this project is to use the ubiquitous nature of certain combinatorial topological objects called maps in order to unveil deep connections between several areas of mathematics.

Amos Korman has been interviewed by Le Monde for his recent results on ants with several co-autors at IRIF.

IRIF organizes the 44th ACM Symposium on Principles of Programming Languages (POPL 2017), Jussieu, Paris, January 15-21, 2017.