The author begins by recalling how he was led in 1923–24 to the ideas of wave mechanics in generalizing the ideas of Einstein's theory of light quanta. He made himself at that time a concrete physical picture of the coexistence of waves and particles and, in 1927, attempted to give them precise form in his “theory of the double solution.” As other ideas prevailed at the time, he abandoned the development of his conception. But for the past twenty years, once (...) again convinced, like Einstein, that present-day quantum mechanics is only a statistical theory and does not give a true picture of physical reality, he has again taken up his old ideas and developed them considerably. He has in particular introduced an element of randomness into the theory and has thus attained to a “hidden thermodynamics of particles,” the results of which appear to be very interesting. (shrink)

Now, this is precisely the experimental law of the photo-electric effect in the form which has been verified in succession for all the radiations from the ultra ...

Cet ouvrage offre aux lecteurs une série de monographies consacrées presque toutes à diverses questions de Physique quantique et de Mécanique ondulatoire. Cet ensemble d'essais étudie l'aspect vraiment nouveau que prennent dans la Physique de l'époque le traditionnel dilemme « continu ou discontinu », la classique opposition de l'élément simple et indivisible avec le continu étendu et divisible. Ces réflexions, révolutionnaires à l'époque, restent aujourd'hui encore d'une étonnante modernité. Dans la science moderne, l'élément simple et indivisible, c'est le grain, grain (...) de matière ou grain de lumière, neutron, électron ou photon. Par contre, dans les théories nouvelles comme dans les anciennes, l'étendue continue et divisible, c'est essentiellement le champ, c'est-à-dire l'ensemble des propriétés physiques qui caractérisent à chaque instant les divers points de l'espace et qui s'expriment par des fonctions généralement continues des coordonnées d'espace et de temps. Mais les conceptions antinomiques de grain et de champ doivent nécessairement en fin de compte venir à la rencontre l'une de l'autre puisqu'elles doivent trouver leur place côte à côte dans le cadre de la Physique totale. Comment les concilier? (shrink)

The general properties of measurements in microphysics are studied and the three types of probabilities that, according to the authors, appear in wave mechanics are set up. Such a distinction, together with the principle of the localization of the corpuscle as was laid down at the very introduction of the theory of the double solution, provides a good grasp of certain phenomena whose explanation according to the usual theory (which makes no use of permanent localization and where the three types (...) of probabilities are intermingled) leads to paradoxical or self-contradictory situations. (shrink)