Re: Speed of light

From: Patrick Powers (frisbieinstein_at_yahoo.com)
Date: 06/02/04 

Date: 2 Jun 2004 02:24:10 -0700

Sam Wormley <swormley1@mchsi.com> wrote in message news:<40BA89F1.B446722@mchsi.com>...
> Patrick Powers wrote:
> >
> > In Feynman's book "QED" he states that the speed of light is a random
> > variable with a normal distribution. The published values of c are
> > averages. This brings to mind some questions.
> >
> > What is the standard deviation? This should not be all that hard to
> > measure. Does the standard deviation increase with time/distance
> > traveled or is it a constant?
>
> Please cite page where Feynman makes a statement about standard
> deviation with respect to light speed.
>
>
> QED Pgs 89-90
>
> "it may surprise you that there ia an amplitude for a photon
> to go at speeds faster or slower than the convetional speed, c.
> The amplitudes for these possibilities are very small compared
> to the contribution from speed c; in fact, they cancel out when
> light light travels over long distances. However, when the
> distances are very short--as in many of the diagrams I will be
> drawing--these other possibilities become vitally important and
> must be considered".
>
> Feynman is referring to interaction on the atomic level.

Aha, this answers my question. What I was interested in is
uncertainty.
The position of a photon is uncertain with a probability distribution.
So is this uncertainty part of the collapse of the wave function or is
the photon actually moving in an uncertain manner? So the former is
true. The mean of the distribution moves steadily at a constant
speed, and there is some true certainty in the situation.

Relevant Pages