A Franco-Mexican exploration at the intersection of epistemic logic and distributed computing

A specialist in distributed computing, Sergio Rajsbaum, a researcher from the Mathematics Institute of the National Autonomous University of Mexico (UNAM), joined École Polytechnique’s Computer Sciences Laboratory (LIX*) in September 2025 for a several-month stay under the Gaspard Monge Visiting Professor program. Enthralled by discovering ever new connections between distributed computing and concurrency with geometry, he has collaborated with Eric Goubault, researcher at LIX, for over a decade on projects exploring these links. 

After meeting at the Workshop on New Connections between Mathematics and Computer Science, organized by Jeremy Gunawardena in Cambridge, UK, in 1995, the two researchers launched a new line of inquiry focusing on the intersections of distributed computing, concurrency, topology, and epistemic logic — a field that has since attracted substantial interest from the global research community. 

Professor Rajsbaum explains that their “research focuses on an interdisciplinary view, exploring the fascinating connection of distributed computing with epistemic logic, investigating the knowledge the computers have of what they know, and the computation of this knowledge.”

His seven-month visit to l’X has enabled Sergio Rajsbaum and Eric Goubault to further develop their research collaboration and organize international workshops. Following a first edition in October, the second workshop took place on June 15-17, 2026, and gathered 40 international researchers and experts in distributed computing, topology, and epistemic logic from prestigious institutions such as Carnegie Mellon, Technion, TU Wien, University of Amsterdam, Heriot-Watt, IRIF, Bern University and University of Minnesota. 

Moreover, their research collaboration sparked the formation of a research group at UNAM, comprising three professors and several students. In addition, “we are also expanding our collaboration with the Philosophy research institute at UNAM, through joint workshops and talks”, explains Sergio Rajsbaum. “These interactions between mathematicians and philosophers—two disciplines with fundamentally different approaches to thinking and writing—are especially valuable, with logic serving as the common denominator.”

Besides working on his research, Professor Rajsbaum also taught classes in the Master Major - Foundations of Computer Science (Institut Polytechnique de Paris) during his stay at École Polytechnique. “Teaching bright, motivated and engaged students” is actually “one of the most rewarding aspects of being an academic professor and researcher”, he says.

Éric Goubault, 
researcher at École Polytechnique, LIX*

Interdisciplinarity and intercultural experiences

Born in Mexico City, where he spent his free time building electronic circuits at the age of 15 before falling in love with mathematics when he discovered analytic geometry, and subsequently with computers following a programming course he took during his Electronic Engineering studies at UNAM, Sergio Rajsbaum has ever since combined his interests in math and computers, with “a deep respect for engineering, which was amplified during his postdoc and research visits at IBM Watson Research Labs and HP Research Labs in USA”. After earning his PhD in Computer Science at Technion- Israeli Institute of Technology, he joined the Institute of Mathematics at UNAM. 
One is tempted to see in Sergio Rajsbaum’s impressive international track record — which led him to many academic institutions worldwide over the years — another expression of his deep curiosity and passion for the intersection of disciplines and the discoveries that interdisciplinarity often sparks. 

“Enjoying collaborating with a wide variety of people”, he highly values intercultural experiences. He has spent time at partner institutions in Canada, the USA, Israel, Chile, Brazil, and France, “building close professional and personal relationships with colleagues abroad, conducting joint research, learning from each other and gaining insights into life and work in other places than [his] hometown, Mexico City.”

UNAM – an important partner institution in Mexico

One of the world's largest universities, the Universidad Nacional Autónoma de México (UNAM) is a public research university in Mexico, which comprises several campuses in Mexico City, various locations across Mexico, as well as a presence in nine countries. The University counts 34 research institutes, 26 museums, and 18 historic sites.

École Polytechnique and the UNAM formalized their partnership by signing a framework cooperation agreement in 2019. Since then, this collaboration has primarily focused on joint research projects in the fields of physics and mathematics. For the current year, this momentum continues with two students from the UNAM arriving at École Polytechnique to complete their research internships, one of whom will be supervised by Eric Goubault.

Enabling l’X to host leading international researchers and foster high-level research collaborations with École Polytechnique’s researchers and laboratories, the Gaspard Monge Visiting Professor Program is supported by the Fondation de l’École polytechnique.

*LIX: a joint research unit CNRS, École Polytechnique - Institut Polytechnique de Paris