's differ only by quantities which are small compared with unity from the values given by the scheme:
These values for the
's characterize the case of the special theory of relativity, i.e. the case of the condition free of gravitation. We shall also assume that, at infinite distances, the
's tend to, and do finally, assume the above values; that is, that matter does not extend into infinite space.
Secondly, we shall assume that the velocities of matter are small compared with the velocity of light, and can be regarded as small quantities of the first order. The quantities
