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- Do photons have relativistic mass? 2 answers
I'm sorry if this question is asked before, but I searched through the site and none satisfied me.
In most of the books I've come across, they just write "rest mass of photon is zero." But never talk about the relativistic Mass. Even in other answers on this site they have written exactly the same.
And once in my class there was some discussion on which I said that Mass of photon is zero, but my teacher corrected me, saying "Rest Mass of photon is 0".
So, what is the real Mass of photon? Or does there even exist something as relativistic Mass of photon?
I know the equation $m\gamma$ gives indeterminate form thus can't be used for photons. And I've no confusion on energy momentum relation which uses the rest mass.