Les Frères Langevin
Program for a fake theater show entitled “Les Frères Langevin” (The Langevin Brothers). Made of heavy cardboard, fake press clippings and paint, it measures 23,8 x 15,7 cm. Date and author unknown.
The French physicist Paul Langevin was one of the first scientists who propounded the theory of the twin paradox, a thought experiment in special relativity involving identical twins. One twin makes a journey into space in a high-speed rocket and returns home to find the other twin, who remained on Earth, has aged more. This result appears puzzling, because each twin sees the other as moving and, so, according to an incorrect application of time dilation and the principle of relativity, each twin should, paradoxically, find the other to have aged less. However, this scenario can be resolved within the standard framework of special relativity: the travelling twin’s trajectory involves two different inertial frames — one for the outbound journey and one for the inbound journey — and so there is no symmetry between the “space-time” paths of the twins. Therefore, the twin paradox is not a paradox in the sense of a logical contradiction. Some references in this program relate to the “Frères Lumière,” who invented cinema. “De retour d’une triomphale tournée à travers toute l’Europe, les Frères Langevin ont la joie de vous présenter leur dernière invention, véritable révolution scientifique grâce à laquelle l’homme devient désormais maître absolu de la matière! Cette naïve et attendrissante ébauche que les Frères Lumière n’hésitaient pas à baptiser pompeusement ‘Cinématographe’ devient aujourd’hui un objet de risée devant le Cinématographoscope des Frères Langevin.”