Radiation pressure does not have anything to do with mass-energy equivalence. 1), the energy for this process does not come from the conversion of electric energy into mass, and 2) having a momentum is not a property tied to massive particles. All electromagnetic waves carry momentum according to Maxwell's theory of electromagnetism, and its transfer is fully explained by his equations and results from the interaction of the EM wave with matter, i.e., absorption and reflection. Each such interaction will transfer momentum to the massive object. This is classical physics, you don't need any Einstein relativity to explain electromagnetic phenomena because his theories only become relevant for very massive bodies and their movement, and nuclear reactions.

[–] subignition@fedia.io 3 points 2 years ago (1 children)

ok, that's quite far over my head but I will take your word for it

[–] Cocodapuf@lemmy.world 3 points 2 years ago* (last edited 2 years ago) (1 children)

Ok, a side note on etiquette here.

When I saw this reply it had a point score of 0, which means somebody downvoted the post.

When a user is freely admitting a lack of expertise, and defers to another user who seems to know better, I would say it's extremely rude to downvote that reply.

This is an example of a user going out of their way to humbly rescind their previous statements when it appears they were mistaken (this is admirable and not a thing that usually happens on the Internet). They didn't do it for their own benefit, but for the benefit of the community, to not leave misleading or incorrect information in the comments.

So to sum up, downvoting a selfless act is pretty shitty and not good for the community.

[–] subignition@fedia.io 2 points 2 years ago

in fairness, I was terse in my original response and probably came off as insincere. Thank you though. I try not to leave up misinformed statements when it turns out to be a learning moment.