On 30 Aug, 07:45, Tom Roberts <tjroberts...@sbcglobal.net> wrote in
sci.physics.relativity:

Chengxian.Zhang wrote:

Dear all,
How to pronounce the the word "Saganc" known as the Sagnac
interferometer.

It is French. The g is almost silent with a sound like an English "y".
In English transliteration: San-yak, but the n is more glottal than
usual, and the "k" is quite soft.

Tom Roberts

You know French Roberts Roberts? Then it was easy for you to
plagiarize Jean-Marc Levy-Leblond and rediscover that special
relativity "would be unaffected" even if "light in vacuum does not
travel at the invariant speed of the Lorentz transform":

http://o.castera.free.fr/pdf/chronogeometrie.pdf
Jean-Marc Levy-Leblond: "D'autre part, nous savons aujourd'hui que
l'invariance de la vitesse de la lumiere est une consequence de la
nullite de la masse du photon. Mais, empiriquement, cette masse, aussi
faible soit son actuelle borne superieure experimentale, ne peut et ne
pourra jamais etre consideree avec certitude comme rigoureusement
nulle. Il se pourrait meme que de futures mesures mettent en evidence
une masse infime, mais non-nulle, du photon ; la lumiere alors n'irait
plus a la "vitesse de la lumiere", ou, plus precisement, la vitesse de
la lumiere, desormais variable, ne s'identifierait plus a la vitesse
limite invariante. Les procedures operationnelles mises en jeu par le
"second postulat" deviendraient caduques ipso facto. La theorie elle-
meme en serait-elle invalidee ? Heureusement, il n'en est rien ; mais,
pour s'en assurer, il convient de la refonder sur des bases plus
solides, et d'ailleurs plus economiques. En verite, le "premier
postulat" suffit, a la condition de l'exploiter a fond."

http://groups.google.ca/group/sci.physics.relativity/browse_frm/thread/8034dc146100e32c?
Tom Roberts: "If it is ultimately discovered that the photon has a
nonzero mass (i.e. light in vacuum does not travel at the invariant
speed of the Lorentz transform), SR would be unaffected but both
Maxwell's equations and QED would be refuted (or rather, their domains
of applicability would be reduced)."

Or perhaps Roberts Roberts you plagiarized Professor Jong-Ping Hsu:

http://www.worldscibooks.com/physics/4114.html
Jong-Ping Hsu: "....unexpected affirmative answer to the long-standing
question of whether it is possible to construct a relativity theory
without postulating the constancy of the speed of light and retaining
only the first postulate of special relativity. This question was
discussed in the early years following the discovery of special
relativity by many physicists, including Ritz, Tolman, Kunz, Comstock
and Pauli, all of whom obtained negative answers."

No matter whom you plagiarized Roberts Roberts, the discovery of
Leblond-Roberts-Hsu is breathtaking, perhaps the most breathtaking
discovery in the history of physics: Whether or not Einstein's light
postulate

http://www.fourmilab.ch/etexts/einstein/specrel/www/"...light is
always propagated in empty space with a definite velocity c which is
independent of the state of motion of the emitting body."

is true, special relativity is correct because special relativity
simply does not need Einstein's light postulate. This also implies
that neither Sagnac's experiment nor any other experiment disproving
Einstein's light postulate can disprove special relativity. Bravo
Leblond bravo Roberts bravo Hsu!

The discovery of Leblond-Roberts-Hsu has been rediscovered lately but,
suprisingly, the original discoverers are reluctant to discuss the new
development on sci.physics.research:

http://groups.google.ca/group/sci.physics.research/browse_frm/thread/92e50228753ef23c?
http://uk.arxiv.org/abs/0708.0929
http://uk.arxiv.org/PS_cache/arxiv/pdf/0708/0708.0929v1.pdf
Relativity Without Tears, Z. K. Silagadze
"Below I will try to show that, combining the ideas from [21, 22, 23,
31], it is possible to make the one postulate derivation of Lorentz
transformations mathematically as simple as was Einstein's original
presentation."

Roberts Roberts why are you reluctant to discuss Silagadze's paper?