Mass Generation of the Proton: A QCD Perspective

The proton’s mass is often assumed to arise directly from the intrinsic masses of the quarks thatcompose it, but this accounts for only a small fraction of its total value. The combined masses ofthe proton’s two up quarks and one down quark contribute roughly 9 MeV, far below theexperimentally measured proton mass of 938 MeV. This discrepancy raises a fundamentalquestion about the true origin of mass in composite particles. This paper examines how themajority of the proton’s mass emerges dynamically from the principles of QuantumChromodynamics (QCD). The relativistic motion of confined quarks, the energy stored in gluonfields, and the nontrivial structure of the QCD vacuum all contribute significantly to the proton’smass through the relationship between energy and mass. Gluon self‑interactions andquark–antiquark condensates further shape the internal energy landscape of the proton. Evidencefrom lattice QCD simulations demonstrates that the proton’s full mass can be reproduced fromfirst‑principles calculations using only quark masses and the strong coupling constant as inputs.These results indicate that most visible mass in the universe arises not from the Higgsmechanism alone, but from the dynamic energy of strong‑force interactions. Understanding theproton’s mass generation therefore provides insight into how QCD governs the structure ofmatter at the most fundamental level.