abstract-navarro – Niels Bohr Archive

Jaume Navarro, University of the Basque Country, Spain
Plumpuddings and Bohr’s atom

Folk history of science speaks about a plum pudding atomic model, formulated by J.J. Thomson with the use of his corpuscles (electrons), which was largely abandoned after Ernest Rutherford's experiments and Niels Bohr's quantum atom. In this paper I explore two related issues: to what extent should we understand Thomson's views as a model for the atom, and what happened with this model in the years after 1913. I will argue that J.J. Thomson did not formulate a consistent atomic model with electrons as the main building block, since his views on electricity, matter and radiation always relied on what he called “Faraday tubes”. These consisted of ether vortical tubes whose properties were meant to explain the mass and electrification of the corpuscles and of the atoms. They also became the physical structures underpinning any explanation of quantum phenomena like atomic spectra, the emission of light and, later on, in the late 1920s, electron diffraction. Thus, the only model he consistently defended were these Faraday tubes rather than a plum pudding atom.