Single-Particle Electrodynamics - Assassination Science

easily understood when one looks at the construction of our electric dipole: if
the rigid stick is precessing, then the two charges have velocities that are equal
and opposite (in circular motion around the centre of the stick, effectively),
of order ε. But the values of their charges, q 1 and q 2 , are also equal and
opposite, and, moreover, are of order ε −1 ; thus, the quantity qv for each of
these charges is of the same sign, and is of order ε 0 . But this qv simply
couples to the magnetic part of the Lorentz force law, qv×B; hence, we are
led to the force (4.9).
If we refer to the part (4.8) of the electric dipole force as the “gradient
force”, then we clearly need to invent a name for the contribution (4.9).
The author considers the term precession force to be a suitable name, since
the force is fundamentally a coupling of the precession of the dipole to the
external magnetic field. A more colourful name might be the term helicopter
force, which evokes images of the particle “taking off” due to its rigid stick
flaying around in the “air” of the magnetic field. Another suitable term might
be the electric dipole Anandan force, because the magnetic dipole dual of
(4.9), highlighted and emphasised by Anandan, has proved controversial in
the last couple of years. Anandan was not the first to discover this force, of
course; but historical precedent suggests that the person or persons who draw
most attention to a phenomenon should have the effect named after them:
for example, Aharonov and Bohm were not the first to suggest the Aharonov–Bohm
effect [74]; Aharonov and Casher were not the first to suggest the
Aharonov–Casher effect [107, 10]; etc. In any case, the author shall, for the
purposes of this thesis, stick to the conservative term “precession force” for
(4.9).
Let us now consider the power into the electric dipole. We shall again
simply add the powers into each electric charge, according to the Lorentz
power expression (2.18),
P = q 1 (v 1·E 1 ) + q 2 (v 2·E 2 );
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