On Wed, 03 Sep 2003 23:08:39 GMT, (HenriWilson) wrote:

Consider a long line of clocks separated by identical rods of length ,say, 100
metres..
C---C---C---C---C---C---C---C---C---C---C---C---C---C

Another identical rod has perpendicular lasers attached to each end, exactly
100 metres apart.

|___|

We will now move the lower rod along the line of clocks at a constant speed and
in close proximity. As its ends pass the clocks, the clocks record the times
the laser beams are detected.

Because no PHYSICAL change occurs in the rod due to motion, (as all SRians will
surely agree) the rod always retains its length of 100 m.


I doubt we all would agree. Anyway, lets take v/c 1 for your sync.
and move on..

Therefore it follows that the LH end of the rod will be aligned with one clock
at exactly the same 'instant in absolute time' as the RH one is aligned with
the next clock.

By subsequently adjusting each adjacent pair of clocks and repeating this in
sequence along the line, it is thus possible to synchronise them all
absolutely.


Absolutely? Use a better word, or leave that word out. Nothing is
absolute. I can always define my own time system different from
yours.. clocks have errors.. etc..

Note: the velocity of the rod is unimportant as long as it is fast enough to
make the laser pulses sufficiently sharp.


Why would you need the rod to move fast? Either the clock detects the
light to threshold or not, this is always sufficiently sharp (it will
just take longer for slower rod)

A true OWLS experiment is now possible using these absolutely synched clocks.

Not quite... how did you measure the speed of the rod?


Henri Wilson.

See my animations and physics book at:
http://www.users.bigpond.com/HeWn/index.htm