Published online by Cambridge University Press: 24 October 2008
The usual method of calculating the probability of a switch between stationary states by the Quantum Mechanics is really equivalent to finding the intensity of the dipole radiation. Other switches of the system not involved in this radiation may be possible but are not taken account of by the calculation. A method of calculating the probability of switches due to radiation by the quadripole moment seems to be supplied by Dirac's recent theory of the interaction between matter and radiation in his paper “The Quantum Theory of Dispersion.” Equations from this paper will be denoted by a D. The results are probably of a purely theoretical interest and the intensities found probably too faint to be observed; but the present considerations do appear to emphasise the need for including the radiation in the exact theoretical treatment of a Quantum Mechanical system.
* Proc. Roy. Soc. A, 114 (1927), pp. 710–728.CrossRefGoogle Scholar
* Schrödinger, , Ann. der Phys. 79, p. 514 (1926).Google Scholar
* Zs. f. Phys. 41, 1927, p. 453.Google Scholar
† Proc. Roy. Soc. A, 115, p. 1 (1927); see p. 5.CrossRefGoogle Scholar
‡ Zs. f. Phys. 43, p. 805 (1927) (see p. 821).CrossRefGoogle Scholar
* For example gives 2{r, s, t; r−1, s−1, t}, the cross terms etc. giving zero. The factor 2 disappears when we normalise.