On Aug 24, 5:46 pm, "Spaceman"
wrote:

<< where $\epsilon_0$ and $\mu_0$ are physical constants
which can be evaluated by performing two simple experiments
which involve measuring the force of attraction between two
fixed changes and two fixed parallel current carrying wires.
According to the relativity principle, these experiments must
yield the same values for $\epsilon_0$ and $\mu_0$ in all
inertial frames. Thus, the speed of light must be the same in
all inertial frames. >>
http://farside.ph.utexas.edu/teaching/em/lectures/node108.html

http://www-ssg.sr.unh.edu/ism/what1.html
http://en.wikipedia.org/wiki/Free_space
http://en.wikipedia.org/wiki/Characteristic_impedance_of_vacuum

<< Problems with emission theory

The simplest form of emission theory says that
radiating objects throw off light with a speed
of "c" relative to their own state of motion,
and (unless we have reason to believe that the
light changes speed in flight), we then expect
light to be moving towards us with a speed that
is offset by the speed of the distant emitter
(c ± v) ). This description generates three
"odd" results:

1. If a radiant star moves across our field
of vision, light given off by differently-moving
atoms in its atmosphere should take different
amounts of time to reach us. Since the retreating
atoms would have a "red" Doppler shift, and the
approaching ones a "blue" Doppler shift, the passing
star might be expected to appear as a "rainbow streak".
2. Similarly, if a radiant star is eclipsed,
one might expect the eclipsing shadow to appear
to intercept different colours of Doppler-shifted
light in sequence - the eclipse might appear to
have coloured fringes.
3. For the case of a double-star system seen
edge-on, light from the approaching star might
be expected to travel faster than light from its
receding companion, and overtake it. If the
distance was great enough for an approaching
star's "fast" signal to catch up with and overtake
the "slow" light that it had emitted earlier when
it was receding, then the image of the star
system should appear completely scrambled. >>
http://en.wikipedia.org/wiki/Emitter_theory

Stop playing with yourself and learn some 21st century physics.
http://nobelprize.org/nobel_prizes/physics/articles/ekspong/index.html
http://farside.ph.utexas.edu/teaching/em/lectures/lectures.html

Sue...