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Evidence for Quark Confinement in the Proton
Xiangdong Ji1, Gerald A Miller2, Chen Yang3
1Tsung-Dao Lee Institute and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 201210, China.
Research (Washington, D.C.)
|August 4, 2026
Summary
Researchers defined and measured the strong interaction force on quarks, providing direct evidence for confinement. This finding advances our understanding of nuclear mass and guides future experiments.
Area of Science:
- * Fundamental forces and particle physics.
- * Quantum chromodynamics (QCD) and nuclear structure.
Background:
- * The strong interaction binds quarks and gluons into protons and neutrons.
- * Quantum chromodynamics (QCD) describes these interactions.
- * Confinement, the inability to observe free quarks, is a key QCD phenomenon yet unproven mathematically.
Purpose of the Study:
- * To define and measure the force on quarks within a proton using experimental data.
- * To provide mathematical evidence for quark confinement.
Main Methods:
- * Utilizing existing experimental data to define and quantify quark-gluon interactions.
- * Analyzing the force experienced by quarks at various positions within the proton.
Main Results:
- * The force on quarks was found to be attractive and constant across a range of distances.
- * This provides direct experimental evidence supporting the theory of confinement in QCD.
Conclusions:
- * The study offers a method to quantitatively understand quark confinement.
- * Findings guide future experiments at electron-ion colliders for deeper insights into nuclear mass origins.
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