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In section 8 of "On the electrodynamics of moving bodies," http://www.fourmilab.ch/etexts/einstein/specrel/www/ , there is a discussion of the fact that the energy of an electromagnetic wave scales by the same Doppler-shift factor as its frequency when you change frames of reference. If this hadn't been true in classical E&M, then there would have been no way for the quantization relation E=hf to be valid in all frames of reference.

What caused me endless confusion was the equation [itex](x-lct)^2+(y-mct)^2+(z-nct)^2=R^2[/itex]. I thought Einstein was talking about an expanding spherical wavefront, and I couldn't make much sense out of anything after that. Finally I decided that he must have been talking about a plane wave, and the sphere is just the shape of a region he's arbitrarily chosen out of the plane wave. Have I got this right? He does say "moving" ("bewegten") with the speed of light, not "expanding" with the speed of light.

If I've got this right, then is the following commentary wrong?

Neuenschwander, http://www.spsnational.org/radiations/2006/ecp_s06.pdf [Broken]

He refers to a "pulse emitted isotropically in all directions." On a more minor note, it seems like the subscripts in eq (23) are a mistake.

I was thinking of contacting Neuenschwander to point out the mistakes, but I wanted to make sure I had it right first.

This may also be helpful: Redzic and Strnad, "Einstein's light complex," http://fizika.phy.hr/fizika_a/av04/a13p113.pdf

Thanks!

-Ben

What caused me endless confusion was the equation [itex](x-lct)^2+(y-mct)^2+(z-nct)^2=R^2[/itex]. I thought Einstein was talking about an expanding spherical wavefront, and I couldn't make much sense out of anything after that. Finally I decided that he must have been talking about a plane wave, and the sphere is just the shape of a region he's arbitrarily chosen out of the plane wave. Have I got this right? He does say "moving" ("bewegten") with the speed of light, not "expanding" with the speed of light.

If I've got this right, then is the following commentary wrong?

Neuenschwander, http://www.spsnational.org/radiations/2006/ecp_s06.pdf [Broken]

He refers to a "pulse emitted isotropically in all directions." On a more minor note, it seems like the subscripts in eq (23) are a mistake.

I was thinking of contacting Neuenschwander to point out the mistakes, but I wanted to make sure I had it right first.

This may also be helpful: Redzic and Strnad, "Einstein's light complex," http://fizika.phy.hr/fizika_a/av04/a13p113.pdf

Thanks!

-Ben

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