The Influence of Retardation on the Londonvan der Waals Forces
Abstract
The influence of retardation on the energy of interaction between two neutral atoms is investigated by means of quantum electrodynamics. As a preliminary step, Part I contains a discussion of the interaction between a neutral atom and a perfectly conducting plane, and it is found that the influence of retardation leads to a reduction of the interaction energy by a correction factor which decreases monotonically with increasing distance R. This factor is equal to unity for R small compared with the wavelengths corresponding to the atomic frequencies, and is proportional to R^{1} for distances large compared with these wavelengths. In the latter case the total interaction energy is given by 3ℏcα8πR^{4}, where α is the static polarizability of the atom. Although the problem of the interaction of two atoms discussed in Part II is much more difficult to handle mathematically, the results are very similar. Again the influence of retardation can be described by a monotonically decreasing correction factor which is equal to unity for small distances and proportional to R^{1} for large distances. In the latter case the energy of interaction is found to be 23ℏcα_{1}α_{2}4πR^{7}.
 Publication:

Physical Review
 Pub Date:
 February 1948
 DOI:
 10.1103/PhysRev.73.360
 Bibcode:
 1948PhRv...73..360C