Re: Light clocks question

From: Harry (harald.vanlintel_at_epfl.ch)
Date: 01/13/05 

Date: Thu, 13 Jan 2005 12:33:50 +0100

"N:dlzc D:aol T:com (dlzc)" <N: dlzc1 D:cox T:net@nospam.com> wrote in
message news:N_nFd.60$jp.17@fed1read01...
> Dear rotchm:
>
> <rotchm@yahoo.com> wrote in message
> news:1105593232.559299.4070@z14g2000cwz.googlegroups.com...
> > How about this explanation. A laser is like a little source of
> > omnidirectional light. The long tube tends to "colmate" the light
> > in a line. But each atom (molecule) in the laser emits in all
> > directions. only the light in a "diagonal" will emenate out from
> > this tube. Thats true for all atoms in the laser. The other
> > "particles" or wavefront just dissipated out of the sides of the
> > laser tube (ever openend a laser to see this plasma light?). Therefore
> > the light always comes out apparently in a vertical manner relative to
> > the train. Hopes this helps
>
> It actually is more simple than that. Lets pretend the laser is one of
> those 10cm x 10 cm x 50 cm brick jobs. The observer on the train sees
this
> brick and the attendant laser spot at right angles to the motion of the
> train. The observer on the embankment sees the laser and spot rotate, at
> an angle that is a function of the train's velocity.
>
> That's why I provided the link I did...
>
> David A. Smith

A little correction: the embankment observer doesn't see the laser rotate!
Nevertheless, indeed that observer sees the lightpath inside the laser
rotate because of the motion of the laser.

Cheers,
Harald

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