Inseparable Twins: A Conversation with Alain Aspect

Abstract

During the third International Ontology Congress, held in October 1998, Alain Aspect, of the Institut d’Optique in Orsay, Paris, gave a lecture on the philosophical implications of his famous experiment. He is noted for his tests of Bell’s inequalities with entangled photons, in which the settings are changed during the flight of the particles. From the early 1980s on, his experimental works on quantum entanglements (“Bell experiments”), single photons, laser cooling of atoms, and quantum simulations have earned him recognitions and awards, including the Gold Medal of the French National Centre for Scientific Research (CNRS), the Wolf Prize in Physics, the Balzan Prize on quantum information, the Niels Bohr Gold medal, and the Albert Einstein medal, among other awards. In 1998, in the context of the third International Ontology Congress, Víctor Gómez Pin, IOC’s Chief Executive Coordinator, discussed with Aspect the philosophical aspects of experimental work in the foundations of quantum mechanics, especially the three experimental tests of John Bell’s inequalities he conducted in 1982, the last of which notably allowed for a choice between the settings on each side to be made during the flight of the photons. The following is a transcription of their conversation, edited by Víctor Gómez-Pin and approved by Alain Aspect.