CHAPTER X
QUANTUM TUBES OF MAGNETIC INDUCTION
“ Si les trajectoires de Bohr n’émettent aucune onde leurs champs
à grande distance doivent être constants. . . . Les quanta ont donc
pour effet de produire à une certaine distance de l’atome un régime
permanent, une organisation des lignes de force en tubes invariable,
analogues à des tourbillons stationnaires en hydrodynamique. Les
conclusions ont une importance particulière au point de vue de
notre conceptions du champ magnétique. Dans la théorie de la
relativité, ce dernier ne se distingue pas essentiellement du champ
électrique ; il se comporte en gros comme un vecteur auxiliaire. La
théorie des quanta lui rend une réalité physique propre, elle nous
conduit à imaginer des tubes d’induction stable multiples d’un tube
unité correspondant au magnéton.”
E. Bauer, C.R., vol. 174, pp. 1335-1338, May 22, 1922
1. Magnetic Tubes threading a Circular Orbit
I N Chapter III it was suggested that the atomicity demanded
by the quantum theory is connected with the existence of
discrete tubes of magnetic induction, the unit tube being deter
mined by the ratio of Planck’s constant to the electron charge.
We now proceed to consider how this view (which was derived
by assuming that the electron possessed not only an electric
charge but also a magnetic moment) may be associated with
Bohr’s conception of a classical electron in a stationary state of
orbital motion.
It seems probable that the result previously obtained as to
the number of magnetic tubes threading the aperture of a ring
electron may be applied also to the case of a classical electron
circulating in a closed orbit. Such an extension has in fact been
suggested in an interesting paper by A. L. Bernoulli * published
in 1916. This author has given an electrodynamic interpreta
tion of Planck’s constant by introducing a principle which he
terms the “ Principle of the Universal Flux of Induction.” The
principle is defined as follows: “If electrons are moving in
* A. L. Bernoulli, Archives des Sciences, vol. 42, p. 24, 1916.
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