Eli5: How can some particles have no mass
In: 42
It’s the other way around, actually.
When particle models were originally formulated, there was a big problem. According to vanilla quantum mechanics, all particles are massless. They measurably aren’t.
That’s why an additional effect had to be bolted onto the Standard Model, later dubbed the Higgs mechanism. A way to give massless particles mass. That’s why discovery of the Higgs Boson was such a big deal in 2012.
All mass comes from “trapped” energy. That’s why less than 1% of a proton’s mass is actually the quarks, the rest is the energy of the bonds between them. Why the mass of two separate atoms after fission is lower than before.
The Higgs mechanism works as a “drag” on particles, like they were moving through something viscous, and that creates a similar effect of “trapping” energy and gives them mass.
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