文档介绍：BELL’S THEOREM : THE NAIVE VIEW OF AN EXPERIMENTALIST†
Alain Aspect
Institut d'Optique Théorique et Appliquée
Bâtiment 503-Centre universitaire d'Orsay
91403 ORSAY Cedex – France
alain.******@-
1. INTRODUCTION
It is a real emotion to participate to this conference memoration of John Bell. I first
met him in 1975, a few months after reading his famous paper1. I had been so strongly
impressed by this paper, that I had immediately decided to do my « thèse d’état » – which
at that time, in France, could be a really long work – on this fascinating problem. I
definitely wanted to carry out an experiment « in which the settings are changed during the
flight of the particles », as suggested in the paper, and I had convinced a young professor
of the Institut d’Optique, Christian Imbert, to support my project and to act as my thesis
advisor. But he had advised me to first go to Geneva, and to discuss my proposal with John
Bell. I got an appointment without delay, and I showed up in John’s office at CERN, very
impressed. While I was explaining my planned experiment, he silently listened.
Eventually, I stopped talking, and the first question came: “Have you a permanent
position?” After my positive answer, he started talking of physics, and he definitely
encouraged me, making it clear that he would consider the implementation of variable
analysers a fundamental improvement. Beyond his celebrated sense of humour, his answer
reminds me of the general atmosphere at that time about raising questions on the
foundations of quantum mechanics. Quite frequently it was open hostility, and in the best
case, it would provoke an ironical reaction: “Quantum Mechanics has been vindicated by
such a large amount of work by the smartest theorists and experimentalists, how can you
hope to find anything with such a simple scheme, in optics, a science of the XIXth
century?” In addition to starting the experiment, I had then to deve