Does the speed of light ONLY partially pass as being ISOTROPIC and that
is all ?

I say partially, because even to this date I know of no actual
measurement methods that do not include either round trip measurements
as part of the test, or do not actually measure speed at all, but
instead perform interference pattern tests as a sort of backup test.

In other words, the speed of light is not being measured
unidirectionally while it is being measured in all directions, and
neither is the speed of light being measured unidirectionally while the
test instruments themselves are moving across space at different test
speeds.


In my search, all I have found so far is an incredibly popular use of
ASSUMPTION.
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-- Einstein's postulate: (a) The speed of light is constant ( The
same in all inertial frames, independent of the motion of the source
and the same in all directions. ).

-- Einstein's postulate: (b) Simultaneity is not an absolute concept
and depends on the frame of reference.

Taking these rules into account, any reliable method used to measure
the speed of light, can not use Simultaneity as part of the test itself
if the test is to be performed in numerous inertial frames.
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The only test I can think of, would be to use two Atomic clocks spaced
far apart on the surface of the earth. Synchronization of the time
readings on these two clocks is not of importance.

At the time when the speed of the earth's orbit around the sun is at
its slowest, one releases photons at the location of Atomic clock # 1.
The time of release is noted. The photons travel across X distance on
the surface of earth, and then reach Atomic clock # 2. The time of
arrival is then also noted.

The difference between the two recorded times readings is noted and is
of final importance. What that the specific difference is in numbers,
is not of importance, but simply the Recording of " a " number, is what
is of value.

At the time when the speed of the earth's orbit around the sun is at
its fastest, the test is repeated. One then checks to see if the
number recorded, being the relative difference between the two time
readings, is still the same as it was when previously measured.

This then determines whether the measurement of the speed of light
produces the same results when the test apparatus is moving at
different velocities across Space.


Does anyone know of any test of this nature has yet been performed ?

THE_ONE