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tardedmemeyesterday at 8:33 PM1 replyview on HN

That is incorrect. Photons have mass. They have no rest mass. They also cannot rest, so you might wonder how relevant that is.


Replies

mr_mitmyesterday at 8:41 PM

The concepts of rest mass and relativistic mass are considered outdated. In modern physics, "mass" means what they meant by "rest mass".

Here some indication I'm not making this up: https://hsm.stackexchange.com/questions/2465/when-and-why-di...

In any case, I never use those concepts, and I know no professional particle physicist that does. By "mass", I mean rest mass.