The wave mechanics of alpha-ray tracks. Offprint from: Proceedings of the Royal Society of London, Vol. A 126. THE QUANTUM THEORY OF MEASUREMENT

MOTT, Nevill Francis

Publication Date: 1929

About this Item

First edition, very rare offprint, of one of the earliest significant papers dealing with the quantum theory of measurment. It "should be considered the earliest innovative attempt to lay the foundations of the theory of environment-induced decoherence, i.e., the dynamical mechanism responsible for the transition to a classical behavior of a quantum particle as a consequence of its interaction with the environment" (Figari, Particle tracks in a cloud chamber: the Mott's conjecture (1929), Atti del XXXVI Convegno annuale SISFA (2017), p. 332). "If an alpha-particle, emerging from a nucleus in an unspecified direction, is to be described by a spherical wave, how is it (the question is posed) that a cloud-chamber track produced by the particle is a well-defined line?" (Pippard, Sir Nevill Francis Mott, C. H. 30 September 1905 - 8 August 1996, Biographical Memoirs of Fellows of the Royal Society 44 (1998), p. 322). "Mott points out that the crucial point is to establish the frontier between the system under consideration and the measuring apparatus. He points out that there are two possible approaches: either one considers the alpha-particle as the quantum system under consideration (and the gas of the chamber as the measuring device) or one chooses to investigate the quantum system consisting of the alpha-particle and of the atoms of the gas. Mott proceeds toward a detailed analysis of the problem following closely the latter approach . . . The model considered by Mott consists of the alpha-particle, initially described by a spherical wave centered at the origin, and the electrons of two hydrogen atoms initially in their ground states. The main result of the paper can be summarized in the following statement: the two hydrogen atoms have negligible probability to be both excited unless the atoms and the radioactive source lie on the same straight line. The result, obtained by only analyzing the Schrödinger dynamics of the entire system and without having any recourse to wave packet reduction, implies that only straight tracks have non-zero probability to be observed in the cloud chamber camera" (Figari, p. 336). Mott's paper was reproduced in the important collection of papers, 'Quantum Theory and Measurement' (Wheeler & Zurek (eds.), 1983). Mott won the Nobel Prize for Physics in 1977 for his work on the electronic structure of magnetic and disordered systems. 8vo, pp. 79-84. Original printed wrappers. Seller Inventory # ABE-1692105440343

Bibliographic Details

Title: The wave mechanics of alpha-ray tracks. ...

Publication Date: 1929

Binding: Soft cover

Condition: Near Fine

Edition: 1st Edition