Re: waves at the speed of light

[Bob LaMontagne <rlamont@POSTOFFICE.PROVIDENCE.EDU>]

I hope we're not talking past each other here. I wasn't considering
measuring a speed. A stationary frequency meter in a lab would suffice.
A sequence of diagonal world lines related to the wave train would
intercept the world line of the probe.

My actual confusion is more with the idea of some sort of an oscillation
intrinsic to the photon - time dilation would wipe out any temporal
variations.  The idea of (spatially?) varying phase, mentioned by a
couple of responders seems closer to what my original posting asked.
Again, I want to read the suggested links - my thoughts aren't focused
enough right now to even properly formulate my concerns.

Thanks,
Bob at PC

"John S. Denker" wrote:
> On 11/12/2003 05:54 PM, Bob LaMontagne wrote:
>  > If I'm measuring the frequency of the photon, I'm staying at the same
>  > spatial position on your diagram and following a path parallel to
>  > the time axis. I don't see how I connect your diagonal line to my
>  > measurement.
>
> Aren't the problem and the solution kinda obvious?
>
> Nevermind photons, nevermind the speed of light.  If
> you're making observations at only one point, so that
> every world line [except the world line of the observer
> itself] is observed at most once, how do you even
> *define* velocity?  How can you assign a velocity to
> *anything* [except for things with zero velocity].
>
> Every definition of velocity I've ever seen has a
> delta_x or a d(x) in the numerator.  It's intrinsically
> a two-point concept.