"One of us is an acrobat and a filmmaker who tries to provoke laughter; the other one tries to contribute to the progress of mathematical physics. Yet, we could endlessly throw our ideas back and forth. The surprising closeness of our approaches, the strange fraternity between our two disciplines, which are as far away from each other in their goals as in their techniques, gave us great joy. It is our feeling of wonder that wed like to share here," write Pierre Etaix and Claude de Calan. Sometimes known as the French Buster Keaton, Pierre Etaix is a master of burlesque and the inventor of unequalled visual gags. Claude de Calan is a scientist at the Centre of Theoretical Physics at the Ecole Polytechnique.