In article t,
hanson wrote:

Case (a):
In news:mbIkb.826385$Ho3.229793@sccrnsc03 or
http://groups.google.com/groups?selm...93%40sccrnsc03
one reads about Prof. Franz Heymann, who AFTER a lifetime of work,
as a teamleader at CERN, went into retirement ......to study GR......
Franz apparently didn't need relativity during his 20 years of daily work
at/with an accelerator that was constructed without the need of SR/GR.

Um, big guy, GR is indeed not needed in the design of an accelerator, but
that doesn't mean SR isn't used. The synchrocyclotron was an early
example. Non-relativistically the cyclotron period is independent of the
particle's momentum, which is convenient until a certain energy when the
period changes enough that no further acceleration is possible. The
synchrocyclotron changes the driving frequency accordingly.


Hence, EL's: "Relativity is nothing but mathematics applied to physics."
appears to hit the button. Or expressed in my own, more colorful world:
"Relativity, like any other theory, is just a ****ing story that attempts to
describe what we see, perceive and measure......after the fact"

I'm not sure how EL's remark applies to relativity but not to other sorts
of physics since Galileo. What else could you say of Galileo timing the
period of a swinging chandelier in church with his pulse, except that he
was applying mathematics to physics? (And that he was bored.) But
relativity has one of the qualities of a good theory -- fecundity. That
is, it's suggested many new experiments to do. Energy versus speed,
momentum versus speed, E=mc^2, the positrons predicted by Dirac,
gravitational redshifting, bending of light around the Sun, time of
flight of radar signals bounced from planets and grazing the Sun, frame
dragging around the Earth... Almost all of that was post-relativity, and
a literature search will reveal a buttload of experiments done or
proposed specifically to test the theories.

--
"Let us learn to dream, gentlemen, then perhaps we shall find the
truth... But let us beware of publishing our dreams before they have been
put to the proof by the waking understanding." -- Friedrich August Kekulé