We discuss our present knowledge of α s, the fundamental running coupling or effective
charge of Quantum Chromodynamics (QCD). A precise understanding of the running of α s …

We review the present theoretical and empirical knowledge for α s, the fundamental
coupling underlying the interactions of quarks and gluons in Quantum Chromodynamics …

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 …

There are two mass generating mechanisms in the standard model of particle physics (SM).
One is related to the Higgs boson and fairly well understood. The other is embedded in …

Using lattice configurations for quantum​​​​​ chromodynamics (QCD) generated with
three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction …

We unify two widely different approaches to understanding the infrared behavior of quantum
chromodynamics (QCD), one essentially phenomenological, based on data, and the other …

Discovered in 1963, the Roper resonance appears to be an exact copy of the proton except
that its mass is 50% greater and it is unstable. These features of the Roper have been very …

After the initial discovery of the so-called “spin crisis in the parton model” in the 1980s, a
large set of polarization data in deep inelastic lepton–nucleon scattering was collected at …

The duality between partonic and hadronic descriptions of physical phenomena is one of the
most remarkable features of strong interaction physics. A classic example of this is in …

We review the present understanding of the spin structure of protons and neutrons, the
fundamental building blocks of nuclei collectively known as nucleons. The field of nucleon …