Quantum Mechanics: from Fundamental Principles to Technological Revolutions

by Prof. Philippe Grangier (Institut d'Optique / CNRS, Université Paris-Saclay)

Monday 26 Oct 2026, 15:00 → 17:00 Europe/Rome

Aula Lepschy (DEI)

In this talk I will present experimental properties of quantum light, as an illustration of the fundamental rules of quantum mechanics: superposition, interferences, and entanglement. Emphasis will be given to experimental tests of Bell's inequalities, that lead to the 2022 Nobel Prize in physics attributed to Aspect, Clauser and Zeilinger. This result opened the way to Quantum Technologies, and as an example I will present and discuss quantum simulators based of arrays of interacting trapped single atoms

Brief CV: Professor Philippe Grangier is a French physicist specializing in quantum optics and the fundamentals of quantum mechanics. He is the Director of Research emeritus at CNRS, working at the Laboratoire Charles Fabry at the Institut d'Optique in Palaiseau.  Grangier’s work has focused on how to generate, measure and utilize single photons and entangled states under controlled laboratory conditions – resources that are key to quantum communication and computing. He was among the group of researchers who, together with Alain Aspect, conducted the seminal experiments of the early 1980s, in which correlations between photons were investigated and tests of Bell’s inequality were performed. These experiments led to the 2022 Nobel Prize in Physics awarded to Alain Aspect, John F. Clauser and Anton Zeilinger. The results obtained were not only of theoretical and philosophical significance but also became the starting point for practical applications: quantum cryptography, quantum teleportation and photonic quantum networks.  During his career from the 1990's until now, Philippe Grangier has carried out a wide range of experiments, including quantum non-demolition measurements, quantum cryptography, the production of single photons and optical Schrödinger cats, and the manipulation of single trapped atoms. He has coordinated many national and European projects, assisting the European Commission in many scientific and logistical aspects of quantum technologies.