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Re: Voting on LIGHT (was energy with Q)



I don't understand what you mean by the "size" of a photon. The
word "size" should imply a measurement of some sort. Here is one way that
you can't measure the size:
Shine a laser beam on an aperture with a shutter and put a photon
counter on the other side of the aperture. Open the shutter for some
time interval, and keep shortening the interval. If the photons had a
size L then there should be no clicks in the counter when the shutter is
open for times shorter that L/c.
The experimental result, I am assured, is that there is no time
interval so short that the beam cuts off. The click rate in the counter
just gets slower and slower as the time interval gets shorter and shorter.
The interpretation is that the shutter merely reduces the probability that
a photon gets through the aperture.
Regards,
Jack

On Wed, 14 Nov 2001, Richard L. Bowman wrote:

At 10:14 AM 11/14/2001 -0400, Tim O'Donnell wrote:
I thought that is pretty clear cut.
Light (all electromagnetic) is comprised of photons (particles)

that also can be treated (modelled) as if they are waves or rays depending
upon the phenomenon under consideration. What I remember is that for a
visible light laser (that is obviously fairly coherent), the envelope
defining the photon is on the order of a meter. Thus there are more than a
million wavelengths of light in such a photon. Can someone else verify
this; it has been a few years since I have looked at this.

Richard Bowman
Dept. of Physics
Bridgewater College, Bridgewater, VA 22812 USA
http://www.bridgewater.edu/~rbowman/


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