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[itex]E = mc^{2}[/itex]

and for photons:

[itex]E = hv[/itex]

Then we can derive an effective mass:

[itex]m = \frac{hv}{c^{2}}[/itex]

And using simple classical gravity obtain:

[itex]hv - \frac{GMm}{r} = hv - \frac{GMhv}{c^{2}r} = Constant[/itex]

You can derive the constant by evaluating the equation above at the limit as r goes to infinity. This then gives you the gravitational red shift, all without using anything from GR.

So, since this prediction is the same for classical AND GR, how can red shift be used as verification of GR? I'm not questioning GR, just wondering why this is still listed as verification when it's clearly not.