🚀 go-pugleaf

On 28 Nov, 18:50, Tom Roberts <tjroberts...@sbcglobal.net> wrote in
sci.physics.relativity:
> John Kennaugh wrote:
> > Oh and what was the 'theoretical justification' of Einstein's second
> > postulate?
>
> He was in essence assuming that Maxwell's equations are an accurate
> description (law of physics) of how physical systems change states.
> Combined with his first postulate (the PoR) that directly implies his
> second postulate. And it also justifies alternate forms of the second
> postulate, such as the speed of light is c in any inertial frame.
>
> Tom Roberts

You avoid mentioning Newton's emission theory of light Roberts Roberts
but your cleverer brother John Norton does not:

http://www.pitt.edu/~jdnorton/homepage/cv.html#forthcoming
"Einstein's Special Theory of Relativity and the Problems in the
Electrodynamics of Moving Bodies that Led him to it." in Cambridge
Companion to Einstein, M. Janssen and C. Lehner, eds., Cambridge
University Press. Preprint.
John Norton: "Einstein could not see how to formulate a fully
relativistic electrodynamics merely using his new device of field
transformations. So he considered the possibility of modifying
Maxwell's electrodynamics in order to bring it into accord with an
emission theory of light, such as Newton had originally conceived.
There was some inevitability in these attempts, as long as he held to
classical (Galilean) kinematics. Imagine that some emitter sends out a
light beam at c. According to this kinematics, an observer who moves
past at v in the opposite direction, will see the emitter moving at v
and the light emitted at c+v. This last fact is the defining
characteristic of an emission theory of light: the velocity of the
emitter is added vectorially to the velocity of light emitted....If an
emission theory can be formulated as a field theory, it would seem to
be unable to determine the future course of processes from their state
in the present. As long as Einstein expected a viable theory of light,
electricity and magnetism to be a field theory, these sorts of
objections would render an emission theory of light inadmissible."

So Roberts Roberts Einstein abandoned the emission theory just because
the FIELD concept of light (CONTINUUM), by producing miracles (time
dilation, length contraction etc.), was going to convert Albert the
Plagiarist into Divine Albert. The emission theory based on Newton's
particle model of light (DISCONTINUUM) could not do so. However at the
end of his life Divine Albert suddenly became honest and made bitter
confessions:

http://discovermagazine.com/2004/sep/einst...start:int=2&-C=
Lee Smolin: "One way to understand this story is to say that
theoretical physics has finally caught up to Einstein. While he was
shunned in his Princeton years as he pursued the unified field theory,
the Institute for Advanced Study, where he worked, is now filled with
theorists who search for new variants of unified field theories. It is
indeed a vindication of sorts for Einstein because much of what
today's string theorists do in practice is play with unified theories
of the kinds that Einstein and his few colleagues invented. The
problem with this picture is that by the end of his life Einstein had
to some extent abandoned his search for a unified field theory. He had
failed to find a version of the theory that did what was most
important to him, which is to explain quantum phenomena in a way that
involved neither measurements nor statistics. In his last years he was
moving on to something even more radical. He proposed giving up the
idea that space and time are continuous. It is fair to say that while
the idea that matter is made of atoms goes back at least to the
Greeks, few before Einstein questioned the smoothness and continuity
of space and time. To one friend, Walter Dallenbäch, he wrote, "The
problem seems to me how one can formulate statements about a
discontinuum without calling on a continuum as an aid; the latter
should be banned from the theory as a supplementary construction not
justified by the essence of the problem, which corresponds to nothing
'real.'"

http://www.perimeterinstitute.ca/pdf/files/975547d7-2d00-433a-b7e3-4a09145525ca.pdf
Albert Einstein: "I consider it entirely possible that physics cannot
be based upon the field concept, that is on continuous structures.
Then nothing will remain of my whole castle in the air, including the
theory of gravitation, but also nothing of the rest of contemporary
physics."

Pentcho Valev
pvalev@yahoo.com