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Eddington already proved that starlight passing our Sun is deflected more according to GR compared to the outcome of Newton. But does this rate of deflection also depend on the frequency the photons has?

A photon doesn't have a rest mass but his energy could perhaps be considered as equivalent to mass. So the higher the energy of the photon the larger the gravity works? Should the answer be the same according to Newtons'law and GR?

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It does not depend on the frequency of the photon. Formally, the deflection angle is a function of the mass of the body deflecting the light (the Sun in your example):

$$ \theta = \frac{4GM}{rc^2} $$

Intuitively, even in Newtonian gravity how much a particle is deflected does not depend on its mass, the reason being the fact that gravitational mass is the same as inertial mass, and so $m a = mGM/r^2$ is the same as $a = GM/r^2$

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  • $\begingroup$ What about the question's argument that energy may be equivalent to mass? Gravitational blue-and redshift definitely depends on wavelength. Refering to your argument at the end: the radial acceleration gravitation exerts certainly depends on the mass of the object. Great question and answer. -- Doesn't that mean that no force is needed for bending, that "this is "curvature"? -- "A naive application of Newtonian gravity can yield exactly half this value..." (Wikipedia) Could that mean that there is no impuls? $\endgroup$
    – Peter Bernhard
    Commented Nov 21, 2022 at 17:49
  • $\begingroup$ @PeterBernhard From what I can read in your comment, you are confusing the mass of the body deflecting the light (symbolized by $M$ above), with the mass of the object being deflected. Photons are massless, but in my last paragraph I argue that, intuitively, the mass of the object being deflected (symbolized by $m$) shouldn't matter. Hopefully that helps $\endgroup$
    – caverac
    Commented Nov 23, 2022 at 21:03
  • $\begingroup$ Thank you! I was aware there is a specific particle - photon, defined by rest mass zero, I do belief though it does depend on its mass "how much a particle is deflected", according to Newtonian law. Anything that weighs 2 kg will be deflected differently as something else that weighs 3 kg, passing along the earth. The formula in my opinion deviates from Newtonian physics and cannot be put into equivalence.This is my last comment, not to be removed to chat, Cheers. $\endgroup$
    – Peter Bernhard
    Commented Nov 24, 2022 at 16:27

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