1925/12/01 by P. A. M. Dirac · 12 citations
Computer Science · Mathematics · Physics and Astronomy · #Action (physics) #Advanced Thermodynamics and Statistical Mechanics #Bohr model #Classical electromagnetism #Classical mechanics #Classical physics #Correspondence principle (sociology) #Mathematics #Physics #Quantum #Quantum Information and Cryptography #Quantum Mechanics and Applications #Quantum mechanics #Stationary state #Theoretical physics
paper · doi:10.1098/rspa.1925.0150
openalex publication_date 1925/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/29
Abstract It is well known that the experimental facts of atomic physics necessitate a departure from the classical theory of electrodynamics in the description of atomic phenomena. This departure takes the form, in Bohr’s theory, of the special assumptions of the existence of stationary states of an atom, in which it does not radiate, and of certain rules, called quantum conditions, which fix the stationary states and the frequencies of the radiation emitted during transitions between them. These assumptions are quite foreign to the classical theory, but have been very successful in the interpretation of a restricted region of atomic phenomena. The only way in which the classical theory is used is through the assumption that the classical laws hold for the description of the motion in the stationary states, although they fail completely during transitions, and the assumption, called the Correspondence Principle, that the classical theory gives the right results in the limiting case when the action per cycle of the system is large compared to Planck’s constant h, and in certain other special cases. In a recent paper Heisenberg puts forward a new theory, which suggests that it is not the equations of classical mechanics that are in any way at fault, but that the mathematical operations by which physical results are deduced from them require modification. All the information supplied by the classical theory can thus be made use of in the new theory.