Emergence of Hadron Mass and Structure

Visible matter is characterised by a single mass scale; namely, the proton mass. The proton's existence and structure are supposed to be described by quantum chromodynamics (QCD); yet, absent Higgs boson couplings, chromodynamics is scale-invariant. Thus, if the Standard Model is truly a part of the theory of Nature, then the proton mass is an emergent feature of QCD; and emergent hadron mass (EHM) must provide the basic link between theory and observation. Nonperturbative tools are necessary if such connections are to be made; and in this context, we sketch recent progress in the application of continuum Schwinger function methods to an array of related problems in hadron and particle physics. Special emphasis is given to the three pillars of EHM-namely, the running gluon mass, process-independent effective charge, and running quark mass; their role in stabilising QCD; and their measurable expressions in a diverse array of observables.

Automated summary

Visible matter is characterized by the proton mass. The emergence of the proton mass in quantum chromodynamics (QCD) links theory and observation. Nonperturbative tools, such as continuum Schwinger function methods, have been applied to problems in hadron and particle physics to establish this connection and explore the role of the running gluon mass, process-independent effective charge, and running quark mass in stabilizing QCD.