Single-Particle Electrodynamics - Assassination Science

apply to canonical quantities, being as they are derived from the Lagrangian
function L or L.
2.5 The canonical–mechanical challenge
The author challenges the reader to pick up an arbitrarily chosen textbook
or research paper from their bookshelf, leaf through the chosen volume, and
count how many times the concepts of canonical quantities and mechanical
quantities are either confused, mistaken for each other, written in ambiguous
or oft-changed notation, or simply not recognised at all.
The reasons for the author’s apparent pedantry, in the preceding sections,
will then be clear.
As a rule, the best authors generally define completely separate symbols
for mechanical and canonical quantities—although the choices made are not
at the present time standardised; good authors generally only mix their notation:
the concepts are clearly understood and enunciated; but less fortunate
authors mix the two types of quantity together with gay abandon, generally
leading to completely meaningless and useless conclusions.
Reader beware!
2.6 Relativistic mechanics
In this section, we consider the various subtleties introduced by the use of
the mechanics of Einstein’s Special theory of Relativity [75]. Again, some
results are simply listed here as an introduction to the author’s notation;
other, more subtle aspects are discussed in somewhat more detail.
2.6.1 Mass
The mass m of a system is a Lorentz scalar, and is defined as the mechanical
energy of the system in the rest frame of the system.
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