Re: A way to measure OWLS...and verify the constancy of the one way speed of light

cj@xxxxxxxxxx (C.J. Luke) wrote in news:42e45f37.55113093@news-
server.cfl.rr.com:

> The concept is easy. Use one clock, two counter circuits, a laser,
> optical receiver, and a one second trigger circuit all co-located in a
> single box. One counter has a preset count that is adjustable that
> once that count has been reached, it will send a *start counting*
> pulse to the second counter. The second counter will start counting
> when it gets that pulse and stop counting when the laser beam is
> *received* at the optical receiver circuit. The length of fiber optic
> cabel is initally attached to the receiving lens for calibration.

Make it simpler. Use an oscilliscope, a laser diode, a 1000 meter length of
fibre cable and a photo diode.

Use a pulse generator, you might save money by using the square wave
calibration signal that most scopes have built in.

You measure the time delay introduced by the fiber cable. You make sure
that moving the cable around [without moving the end of the cable away from
the photodiode] has no effect on the delay introduced by the cable.

You then start to move the end of the cable away from the photodiode and
measure the INCREASE in delay.

That increase is the one way speed of light.

If you fasten the end of the cable to the edge of a rotating wheel, you can
even determine if c'=c+/-v is valid. You will need to introduce a coupling
into the cable to allow the rotation, but the delay introduced by the
coupling can be tested and accounted for.




--
bz

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+sp@xxxxxxxxxxxxxxxxxxxx remove ch100-5 to avoid spam trap
.

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