>>>But in my theory, light that has traveled hundreds of millions of years acts different, and doesn't fit on the same EM spectrum as fresh locally emitted light.
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>>>It suggests that frequency can drop in really old light, and the wavelength does NOT go up.
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>>How would that be possible? The speed of ANY wave - not only EM waves - must always be the product of wavelength * frequency. This is not advanced math, but simple geometrical reasoning. You can't circumvent that.
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>Sure you can.
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>Wavelength and frequency are classical concepts.
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>My code constitutes a very non-classical physics.
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>Remember the wave-particle duality?
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>EM "waves" are different than sound waves or ocean waves, or anything like that.
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>> For example, if light goes at 300,000 km/sec, and the frequency is one second, you'll have one wave crest every 300,000 km, since that is the distance the previous wave crest advanced in one second.
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>>Nor have countless experiments produced any evidence that light goes at any speed but "c".
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>How about this:
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>"Delayed gamma rays from deep space may provide the first evidence for physics beyond current theories."
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>http://www.physorg.com/news110480559.html
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>It seems to corroborate my hypothesis.
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>>>If anyone can think of a way to test that, it would be pretty good proof.
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>>It should be possible, in principle, to shine a laser from the moon, or perhaps from a spacecraft further away, and measure any change in frequency. But I guess that first there would have to be a sound theory to justify such an experiment.
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>We need to test it at distances where Hubble redshift is observed, hundreds of millions of light years.
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>An experiment that involved us emitting the light would have to take hundreds of millions of years to complete.
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>That's not going to work.

Sure it can work, unless you assume that any change happens suddenly, which you didn't mention. Assuming that light ages gradually, i.e. that the frequency gradually reduces, then it should do so every second, albeit by a small amount. I think it should be possible to measure that, even over a distance of a few light-seconds (or perhaps light-hours).

Of course, any such measurement has to take into account other factors, which are known to affect the frequency of light: Doppler effect (the Moon's orbit isn't exactly circular), and gravitational effects (Earth has a stronger attraction than our Moon - light from the Moon would appear to have a slightly higher frequency by this effect alone).

I understand that time measurements are currently based on measurements of some frequency, and that these can be done with an extremely high accuracy - must be something like 1e-10 or so.