Single-Particle Electrodynamics - Assassination Science

of this chapter. After they were obtained, the author became aware of the
Cohn–Wiebe paper. As might be expected, the author had chosen a different
set of “convenient quantities” with which to express his results than did
Cohn and Wiebe; but, nevertheless, the fundamental quantities used in the
computations were basically compatible. (There is considerable freedom in
deciding how one is to treat the internal degrees of freedom of the dipole moments;
this is partially the reason why some of the earlier results are difficult
to interpret, intuitively.) After some work (now presented in Appendix D),
the author was able to verify that his manifestly-covariant expressions were,
indeed, in all ways equivalent to those of Cohn and Wiebe (and, consequently,
to those of their predecessors).
However, the author wished to take the problem one step further: namely,
an evaluation of the retarded field expressions in terms of the explicit, noncovariant
quantities, such as v, ˙v, σ, ˙σ, etc., that are used to great effect
in the Thomas–Bargmann–Michel–Telegdi equation. When the author’s attempt
towards this end was first begun,—by using the identities, derived by
the author, now listed in Section G.4,—the resulting expressions were horrendous.
But then, bit by bit, many of the terms began to cancel out with each
other; and, after some further pain, the author found a number of additional
quantities (specifically, the vectors n ′ and n ′′ , to be introduced later; and,
most importantly, the FitzGerald spin vector σ ′ ) that simplified the results
remarkably. The net result is that the expressions found by the author are
not only built out of quantities (such as ˙v) that one can understand intuitively,
they furthermore are actually simpler than the manifestly-covariant
expressions from which they are derived. This was an unexpected bonus.
Finally, while writing the computer algebra program radreact to complete
the horrendously complicated algebraic computations of the radiation
reaction calculations of Chapter 6, the author made a slight detour, and
wrote another small program, using the same algebra libraries, to comprehensively
check the results of this chapter (see Section G.2.2), starting with the
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