These articles and speeches by the Nobel Prize-winning physicist date from 1934 to 1958. Rather than expositions on quantum physics, the papers are philosophical in nature, exploring the relevance of atomic physics to many areas of human endeavor. Includes an essay in which Bohr and Einstein discuss quantum and_wave equation theories. 1961 edition.
Introductory survey -- Atomic theory and mechanics -- The quantum postulate and the recent development of atomic theory -- The quantum of action and the description of nature -- The atomic theory and the fundamental principles underlying the description of nature.
Quantum physics and philosophy--causality and complementarity -- The unit of human knowledge -- The connection between the sciences -- Light and life revisited -- The Rutherford memorial lecture 1958 -- The genesis of quantum mechanics -- The Solvay meetings and the development of quantum physics.
SummaryA short exposition is given of the foundation of the causal description in classical physics and the failure of the principle of causality in coping with atomic phenomena. It is emphasized that the individuality of the quantum processes excludes a separation between a behaviour of the atomic objects and their interaction with the measuring instruments denning the conditions under which the phenomena appear. This circumstance forces us to recognize a novel relationship, conveniently termed complementarity, between empirical evidence obtained under different (...) experimental conditions. An appropriate tool for a complementary mode of description is provided by the quantum‐mechanical formalism which allows us to account for regularities of definite or statistical character beyond the grasp of classical physical explanation. – N. B. (shrink)
v. 1. Atomic theory and the description of nature -- v. 2. Essays 1932-1957 on atomic physics and human knowledge -- v. 3. Essays 1958-1962 on atomic physics and human knowledge -- v. 4. Causality and complementarity.
The paper presents a revised view of quantum mechanics centered on the notion (“genuine fortuitousness”) that the click in a counter is a totally lawless event, which comes by itself. A crucial point is the distinction between events on the spacetime scene and the content of the symbolic algorism. A revised conception of matrix variables emerges, by which such a variable, as part of a whole, does not have a value, under any circumstance. This conception is at variance with that (...) of indeterminate variables. A matrix variable not having a value does not enter spacetime and is not a measurable quantity, but manifests itself by a click in a counter with the remarkable property of having an onset, a beginning, from which the click develops. The individual click with its immense complexity is unique and lawless, even beyond probability. The notion of probability only applies to clicks in low resolution, and the completeness of a probabilistic theory is thereby seen in a new perspective. The genuinely fortuitous click is not produced by the impact of a particle, nor caused by an event in the source prior to the click in the counter. Indeed, there are no particles on the spacetime scene. The theory is thereby liberated from notions, which go with particles having indeterminate variables, and which have given to quantum mechanics the image of an unfathomable theory. With no particle as intermediary, the connection between source and detector is non-local, as is the entire theory, which deals exclusively with distributions of clicks. The locality permeating quantum mechanics is a symbolic one. The wave function enters in the sole role of encoding the probability distributions of clicks. The quest to understand the occurrence of the click in terms of the evolution of the wave function loses its meaning. However, click distributions in low resolution can be analyzed in terms of the connection between click distributions for different sets of counters, as given by the wave function. With increasing resolution, the probabilities, and the wave function, gradually lose significance, whereby the onset remains beyond reach. Thus, the downward path from events on the spacetime scene does not extend beyond the onset. The notion that quantum mechanics deals with particles (or fields) is rooted in the historical evolution but appears unable to accomodate genuine fortuitousness. The latter concept is given its due place by fully accepting the abstract nature of the matrix variables. (shrink)
Introduction -- Light and life -- Biology and atomic physics -- Natural philosophy and human cultures -- Discussion with Einstein on epistemological problems in atomic physics -- Unity of knowledge -- Atoms and human knowledge -- Physical science and the problem of life.
The present article reports on the finding of the principle behind quantum mechanics. The principle, referred to as genuine fortuitousness, implies that the basic event, a click in a counter, comes without any cause and thus as a discontinuity in spacetime. From this principle, the formalism of quantum mechanics emerges with a radically new content, no longer dealing with things to be measured. Instead, quantum mechanics is recognized as the theory of distributions of uncaused clicks that form patterns laid down (...) by spacetime symmetry and is thereby revealed as a subject of unexpected simplicity and beauty. The departure from usual quantum mechanics is strikingly borne out by the absence of Planck's constant from the theory. The elimination of indeterminate particles as cause for the clicks, which the principle of genuine fortuitousness implies, is analogous to the elimination of the ether implied by the principle of relativity. (shrink)