Abstract Einstein receive a letter from Bose and developed his idea into Bose–Einstein statistics. He also used De Broglie’s idea to clarify wave-particle duality. De Broglie also inspired Schrödinger to develop his equation in quantum mechanics. Bothe and Geiger ruled out Bohr’s BKS theory experimentally. Heisenberg came up with wave mechanics on the island of Heligoland. Born and Jordan realised that matrices were the mathematical key to quantum mechanics. Schrödinger developed an equivalent formalism. Heisenberg formulated his uncertainty principle. The Solvay Conference in Brussels in October 1927 was the scene for the famous Einstein–Bohr showdown, in which Bohr refuted Einstein’s thought experiment calculated to show that quantum mechanics was incomplete, a subject to which Einstein would return years later in the EPR paper. In Brussels, Einstein met Elisabeth Queen of the Belgians, a violinist with whom he would play chamber music many times. Einstein collaborated with Emil Rupp on experiments to explore quantum effects. Rupp turned out to be a charlatan who duped Einstein with fabricated results. Einstein became involved with the academic politics of the Hebrew University of Jerusalem, and clashed with its head, Judah Magnes.
Abstract Einstein receive a letter from Bose and developed his idea into Bose–Einstein statistics. He also used De Broglie’s idea to clarify wave-particle duality. De Broglie also inspired Schrödinger to develop his equation in quantum mechanics. Bothe and Geiger ruled out Bohr’s BKS theory experimentally. Heisenberg came up with wave mechanics on the island of Heligoland. Born and Jordan realised that matrices were the mathematical key to quantum mechanics. Schrödinger developed an equivalent formalism. Heisenberg formulated his uncertainty principle. The Solvay Conference in Brussels in October 1927 was the scene for the famous Einstein–Bohr showdown, in which Bohr refuted Einstein’s thought experiment calculated to show that quantum mechanics was incomplete, a subject to which Einstein would return years later in the EPR paper. In Brussels, Einstein met Elisabeth Queen of the Belgians, a violinist with whom he would play chamber music many times. Einstein collaborated with Emil Rupp on experiments to explore quantum effects. Rupp turned out to be a charlatan who duped Einstein with fabricated results. Einstein became involved with the academic politics of the Hebrew University of Jerusalem, and clashed with its head, Judah Magnes.
The Bohr-Einstein debate, the most interesting intellectual contest in science of this century, began in the late afternoon of October 24,1927, at the Fifth Solvay Conference in Brussels, Belgium. 50 (Einstein had not attended the meeting in Como a month before, at which Bohr first introduced complementarity.) The theorists Bohr, Born, de Broglie, Brillouin, Dirac, Einstein, Ehrenfest, Heisenberg, Pauli, Planck, and Schrödinger were in attendance, as well as the experimentalists Bragg, Compton, Madame Curie, and Debye. The eminent Dutch theorist H.A. Lorentz, the grandfather of relativity (after whom the theory’s space-time transformations were named), chaired the sessions. The organizers had chosen “Electrons and Photons” as the official title of the conference, but a better one might have been: “Quantum Mechanics: What Does it Mean?” As Einstein’s opinion had become widely known, fireworks were expected. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
Abstract This conference was lauded by Heisenberg as, “officially, the completion of the quantum theory,” while Langevin remarked it was, “where the confusion of ideas reached its peak.” The conference was held just as the theory had reached maturity, only two years after Heisenberg’s matrix mechanics was invented. De Broglie argued for his pilot wave theory, which was shot down by Pauli using an incorrect argument and in later years was re-introduced as the de Broglie–Bohm theory. Heisenberg and Dirac debated the meaning of superposition and the “collapse” of the wave function. Bohr and Einstein engaged in their legendary debate. In the conference proceedings, we see the main contributors to the new theory attempt to come to terms with its enigmas.
Between 1927 and 1936 no one had a greater influence on Bohr's thinking than Einstein. It was Einstein's unremitting criticism which provided the severest test of Bohr's interpretation of quantum physics, and which forced him to clarify and refine his arguments. The debate between Bohr and Einstein concerning the interpretation of quantum physics is generally recognised as one of the great intellectual disputes in the history of science. What was the nature of the disagreement between them, and what were the arguments with which each defended his position? The fifth Solvay Conference, 1927 Einstein was not present at the Volta Centennial Conference at Como in September 1927, where Bohr first presented his theory of complementarity; Einstein first learned of Bohr's interpretation of quantum mechanics at the fifth Solvay Conference of Physics at Brussels in October 1927. In the discussion following Bohr's paper Einstein examined an imaginary experiment in which an electron passes through a slit in a diaphragm and impinges at a point on a hemispherical screen. This experiment, Einstein suggested, could be interpreted in either of two ways: the de Broglie–Schrödinger waves represent either ( a ) an ensemble of electrons spread out in space (but not an individual electron), or ( b ) a wave-packet corresponding to an individual electron. There is, he noted, a difficulty with the latter interpretation.
Schrödinger's work on wave mechanics in 1926 appears to have been driven by the idea that one could give a purely wave-theoretical description of matter. Key elements in this picture were the idea of particles as wave packets (Section 4.3) and the possible implications for the problem of radiation (Section 4.4). This pure wave theory, in contrast to de Broglie's work, did away with the idea of particle trajectories altogether (Section 4.5). The main conflict, however, was between Schrödinger and the proponents of quantum mechanics (in particular Heisenberg, Section 4.6), both in its form at the time of Schrödinger's papers and in its further developments as sketched in the previous chapter. For reference, we provide a brief chronology of Schrödinger's writings relating to wave mechanics up to the Solvay conference: Paper on Einstein's gas theory, submitted 15 December 1925, published 1 March 1926 (Schrödinger 1926a). First paper on quantisation, submitted 27 January 1926, addendum in proof 28 February 1926, published 13 March 1926 (Schrödinger 1926b). Second paper on quantisation, submitted 23 February 1926, published 6 April 1926 (Schrödinger 1926c). Paper on the relation between wave and matrix mechanics (‘equivalence paper’), submitted 18 March 1926, published 4 May 1926 (Schrödinger 1926d). Paper on micro- and macromechanics (coherent states for the harmonic oscillator), published 9 July 1926 (Schrödinger 1926e). […]
On October 24th, 1927, the world's most important physicists met in Brussels for what is known as the fifth edition of the Solvay Conference. The focus of the discussion was the new Quantum Mechanics, to which most of the people present at the meeting had contributed but about which they had contrasting opinions. On the one hand, Niels Bohr and Werner Heisenberg claimed they had provided the new science with a definite structure, not subject to further modifications, while on the other, eminent figures such as Erwin Schrodinger and Albert Einstein believed that the theories put forward by the so called Copenhagen School, of which Bohr and Heisenberg were the most important exponents, were incorrect or at least incomplete.
Abstract This chapter examines some crucial experiments and basic principles of quantum mechanics that have strongly influenced the development of quantum theory in its modern form: starting from Planck’s law of black-body radiation and its derivation using the quantization of energy; Einstein’s photon hypothesis for the puzzle presented by the photoelectric effect and its test via the Millikan experiment; the Compton effect; Bohr’s theses for the structure of the hydrogen atom and the complementarity of waves and particles i.e., the wave-particle duality, culminating in de Broglie’s ideas for matter waves and their confirmation in the Davisson-Germer experiment for electron diffraction from a crystal; Heisenberg’s uncertainty principle for position and momentum as well as for energy an time; the famous double-slit experiment and Born’s probability interpretation, and finally the provocative thought experiment of Schrödinger’s cat