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arXiv · 2211.09905

Origin of the Proton Mass

Abstract

Atomic nuclei lie at the core of everything visible; and at the first level of approximation, their atomic weights are simply the sum of the masses of all the neutrons and protons (nucleons) they contain. Each nucleon has a mass $m_N \approx 1\,{\rm GeV}\approx 2000$-times the electron mass. The Higgs boson -- discovered at the large hadron collider in 2012, a decade ago -- produces the latter, but what generates the nucleon mass? This is a pivotal question. The answer is widely supposed to lie within quantum chromodynamics (QCD), the strong-interaction piece of the Standard Model. Yet, it is far from obvious. In fact, removing Higgs-boson couplings into QCD, one arrives at a scale invariant theory, which, classically, can't support any masses at all. This contribution sketches forty years of developments in QCD, which suggest a solution to the puzzle, and highlight some of the experiments that can validate the picture.

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Craig D. Roberts. 2022-11-17. Origin of the Proton Mass. https://doi.org/10.1051/epjconf%2F202328201006

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