Support l'X International Research Collaboration on Quantum Physics with Visiting Professor Igor Klep
The Gaspard Monge Visiting Professor program allows École Polytechnique to host internationally renowned researchers and professors for high-level collaborative teaching and research projects within its laboratories. Through this initiative, Igor Klep, an incisive and internationally recognized mathematician known for his contributions to functional analysis, operator algebra, and polynomial optimization, is joining École Polytechnique’s Computer Science Laboratory (LIX*) and the institution’s Center for Theoretical Physics (CPHT) as a Gaspard Monge Visiting Professor.
A faculty member at both the Faculty of Mathematics and Physics at the University of Ljubljana and the Faculty of Mathematics, Natural Sciences and Information Technologies at the University of Primorska, Igor Klep collaborates with PhIQus, a joint research group between LIX, CNRS, Inria Saclay, and École Polytechnique’s Centre for Theoretical Physics (CPHT).
PhIQus explores the intersection of physics, information theory, and quantum simulation, under the leadership of Marc-Olivier Renou, Junior Professor Chair at Inria Saclay and affiliated researcher at LIX and CPHT. As the group explores new frontiers in quantum information processing, it adopts a multi-disciplinary approach that integrates quantum information theory, theoretical computer science, and the mathematical frameworks of C*-algebras and non-commutative polynomial optimization.
A recognized specialist in functional analysis and mathematical optimization, Igor Klep contributes his expertise to this research. He and Marc-Olivier Renou had previously initiated discussions on applying Klep’s mathematical tools to quantum physics. Thanks to the Gaspard Monge Visiting Professorship program, they can now deepen this collaboration and explore how non-commutative algebra - an area in which Klep has played a leading role - can be applied to problems in quantum information theory.
Beginning with challenges identified by the PhIQus research group, the two scientists “discuss how to adapt the framework of polynomial optimization to solve them”, explains Igor Klep, emphasizing the collaborative value of this partnership. “The opportunity to interact closely with experts in this discipline at École Polytechnique provides unique perspectives and novel approaches that will benefit us all”, he stresses.
At the intersection of Physics, Information Theory, and Quantum Simulation
Within the École Polytechnique’s Computer Science Laboratory (LIX), Igor Klep collaborates with the PhIQus research group led by Marc-Olivier Renou, whose research focuses on the distinctive capabilities of quantum systems for information processing, particularly within quantum networks and distributed computing. His work covers fundamental distinctions between classical and quantum information theory, identifying key tasks that illustrate these differences and developing protocols for experimental implementation.
As his research approach combines quantum information theory, theoretical computer science, but also mathematical tools like C*-algebras and non-commutative polynomial optimization, Marc-Olivier Renou declares that “the collaboration with Igor is determinant, as adapting these mathematical tools to our areas of research requires both deep mathematical expertise and a strong understanding of quantum information theory”.
“Mastering both is nearly impossible for one person, so solving these challenges necessitates collaboration”, he explains. “Understanding how these adaptations can be achieved takes time. The Gaspard Monge Visiting Professorship program enables us to work closely with Igor during his stay and gives us a unique opportunity for almost daily discussions”.
Together with other partners, Igor Klep and Marc-Olivier were awarded a prestigious QuantERA research grant for their project COMPUTE. They aim to drive the future development of quantum networks by applying noncommutative polynomial optimization to problems arising in quantum networks. An interdisciplinary approach is at the very heart of the project, as it crosses the traditional boundaries between the polynomial optimisation and quantum information communities by making the former’s tools accessible to the latter and the latter’s challenges available to the former.
Additional, international expertise from Slovenia
Professor Igor Klep’s activities during his Gaspard Monge Visiting Professorship at École Polytechnique encompass three dimensions: research, teaching, and organizing a seminar series. Additionally, he and Marc-Olivier Renou co-organized a workshop on Operator Theory and Polynomial Optimization in Quantum Information Theory, held at the Physics Centre in Bad Honnef in March 2025. Further workshops are planned during his stay, focusing on non-commutative polynomial optimization and its applications to quantum information theory, particularly in the context of quantum networks and aspects of condensed matter physics.
Since joining École Polytechnique in February 2025, Professor Klep has also been teaching. He currently delivers three courses: Advanced Topics in Quantum Information Theory, Large-Scale Mathematical Optimization, and Decision Theory with Applications to Energy Systems. He considers “teaching at École Polytechnique a prestigious opportunity” that allows him “to contribute to the development of bright young researchers and practitioners in mathematics and quantum information theory.” Moreover, Professor Igor Klep emphasizes that “the interaction with students and the ability to inspire them through advanced courses and seminars is particularly meaningful and fulfilling” for him.
Supported by the Fondation de l’École polytechnique, the Gaspard Monge Visiting Professor Program enables the institution to host leading international researchers and foster high-level research collaboration with École Polytechnique’s researchers and laboratories.
the As visiting professors spend several months on campus, they are often accompanied by postdoctoral researchers, who also benefit from the immersive research environment at École Polytechnique while bringing valuable international perspectives. Accordingly, École Polytechnique has extended its invitation to two postdoctoral researchers Professor Klep closely works with at the University of Ljubljana.
*LIX: a joint research unit in computer science between CNRS, École Polytechnique - Institut Polytechnique de Paris