Quantum World

Bernard d’Espagnat (22 August 1921 - 1 August 2015), after spending time at the École Polytechnique and a few years at the French National Centre for Scientific Research (CNRS) with stints abroad, contributed to the creation of the theoretical physics research group at CERN (Geneva) and conducted research in elementary particles physics. Professor at the Paris-Orsay University, he continued his research in this field while developing an interest in the conceptual foundations of quantum mechanics. He organized workshops on this theme in 1970 in Varenna (Italy) and in 1976 in Erice (Sicily) (the latter in collaboration with John Bell) focusing mainly on quantum entanglement and non-locality, which was then in the process of being verified experimentally, and which he subsequently investigated further. His main works are: Conceptual Foundations of Quantum Mechanics (W.A. Benjamin, 1971), À la recherche du réel. Le regard d’un physicien (Gauthier-Villars, 1979), Un atome de sagesse (Seuil, 1982), Le Réel voilé. Analyse des concepts quantiques (Fayard, 1994), Traité de physique et de philosophie (Fayard, 2002). He was a member of the Institute Académie des Sciences Morales et Politiques.Hervé Zwirn, is a physicist and epistemologist, and a senior researcher at the CNRS (the French National Centre for Scientific Research). He is a visiting researcher at the Institute of History and Philosophy of Sciences and Technology (IHPST, Paris1, CNRS & ENS), at the Research Centre for Applied Maths (CMLA, CNRS & ENS Cachan) and at the Paris Interdisciplinary Energy Research Institute (LIED, CNRS & Paris 7). His research focuses mainly on the interpretations of quantum mechanics and their philosophical consequences, on the axiomatic formalization of inference modes and on the behaviour of complex systems. He also proposed a model of the theoretical decision-making process using the mathematical framework of quantum mechanics. He is executive director of the Consortium de Valorisation Thématique de l'Alliance Athéna (UMS 3599, CNRS & Paris4), responsible for the commercial development and dissemination of the research output in social sciences of French laboratories. His main books are: Les Limites de la connaissance (Odile Jacob, 2000), Les Systèmes complexes (Odile Jacob, 2006), Philosophie de la mécanique quantique (with Jean Bricmont, Vuibert, 2009), Qu’appelle-t-on aujourd’hui les sciences de la complexité? (with Gérard Weishbuch, Vuibert, 2010).

• Introduction.- A Journey through the Quantum World (Bernard d’Espagnat & Hervé Zwirn).- The inescapable strangeness of the quantum world (Édouard Brézin).- Quantum physics appearance and reality, Exchange of views.- Experimental aspects of decoherence (Jean-Michel Raimond).- Theoretical aspects of decoherence, Exchange of views.- The Pilot Wave Theory of Louis de Broglie and David Bohm (Franck Laloë).- The Pilot Wave Theory: problems and difficulties (Franck Laloë).- Relational interpretation of quantum mechanics and the EPR paradox (Matteo Smerlak).- Exchange of views on the relational interpretation and Bell.- The theory of measurement (Roger Balian).- The loop quantum gravity (Carlo Rovelli).