and
denote the space indices only.
On the right-hand side of (116) we can replace 1 +
by 1 and
by
. It is easy to see, in addition, that to this degree of approximation we must put
and
denote the space indices only.
On the right-hand side of (116) we can replace 1 +
by 1 and
by
. It is easy to see, in addition, that to this degree of approximation we must put