Force of gravity between photon and earth

AI Thread Summary
Using F=(GMm)/(r^2) to calculate the gravitational force between a photon and the Earth is not straightforward, as photons are massless particles. The discussion references the Mossbauer Effect experiments, which measured energy changes of photons in a gravitational field, highlighting the complexities involved in such calculations. It also notes that the observed deflection of light by gravity is twice what Newtonian physics would predict, aligning with General Relativity. For accurate calculations, both Newtonian and relativistic approaches should be considered. Understanding these principles is essential for grasping the interaction between light and gravity.
cragar
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If I wanted to use F=(GMm)/(r^2) to find the force between a photon and the Earth
could I use E=hf and then find the energy the plug it into E=mc^2 then use the to find
the mass equivalence and then plug it into the first equation.
would this work.
 
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Not really, the observed deflection is twice that. That was one of the early tests of GR.
 
so then how would we calculate it .
 
Review the google websites discussing the famous Mossbauer Effect experiments by Pound and Rebka at Harvard in 1959, where they measured the energy gain of the 14 keV photons from iron-57 falling from the top of the physics building to the basement.
 
cragar said:
so then how would we calculate it .

Bending Light gives both Newtonian and relativistic calculations.
 
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