Here’s another supposed technobabbler...
It is known that Maxwell’s electrodynamics—as usually understood at the
present time—when applied to moving bodies, leads to asymmetries which do
not appear to be inherent in the phenomena. Take, for example, the
reciprocal electrodynamic action of a magnet and a conductor. The
observable phenomenon here depends only on the relative motion of the
conductor and the magnet, whereas the customary view draws a sharp
distinction between the two cases in which either the one or the other of
these bodies is in motion. For if the magnet is in motion and the conductor
at rest, there arises in the neighbourhood of the magnet an electric field
with a certain definite energy, producing a current at the places where
parts of the conductor are situated. But if the magnet is stationary and
the conductor in motion, no electric field arises in the neighbourhood of
the magnet. In the conductor, however, we find an electromotive force, to
which in itself there is no corresponding energy, but which gives
rise—assuming equality of relative motion in the two cases discussed—to
electric currents of the same path and intensity as those produced by the
electric forces in the former case.
Examples of this sort, together with the unsuccessful attempts to discover
any motion of the earth relatively to the “light medium,” suggest that the
phenomena of electrodynamics as well as of mechanics possess no properties
corresponding to the idea of absolute rest. They suggest rather that, as
has already been shown to the first order of small quantities, the same
laws of electrodynamics and optics will be valid for all frames of
reference for which the equations of mechanics hold good.1 We will raise
this conjecture (the purport of which will hereafter be called the
“Principle of Relativity”) to the status of a postulate, and also introduce
another postulate, which is only apparently irreconcilable with the former,
namely, that light is always propagated in empty space with a definite
velocity c which is independent of the state of motion of the emitting
body. These two postulates suffice for the attainment of a simple and
consistent theory of the electrodynamics of moving bodies based on
Maxwell’s theory for stationary bodies. The introduction of a “luminiferous
ether” will prove to be superfluous inasmuch as the view here to be
developed will not require an “absolutely stationary space” provided with
special properties, nor assign a velocity-vector to a point of the empty
space in which electromagnetic processes take place.
The theory to be developed is based—like all electrodynamics—on the
kinematics of the rigid body, since the assertions of any such theory have
to do with the relationships between rigid bodies (systems of
co-ordinates), clocks, and electromagnetic processes. Insufficient
consideration of this circumstance lies at the root of the difficulties
which the electrodynamics of moving bodies at present encounters.
The rest of paper is here:
https://www.fourmilab.ch/etexts/einstein/specrel/www/