Speaker
Description
Lattice QCD is advancing our understanding of nucleon structure across a wide range of observables, tied together by a common goal: resolving how momentum and forces are distributed among quarks and gluons. I will begin with recent high-precision determinations of the isovector axial, scalar, and tensor charges, where a comprehensive treatment of systematic uncertainties is enabling meaningful comparisons with experiment. Turning to the gluon momentum fraction, I will highlight progress in nonperturbative renormalisation and the treatment of quark-gluon mixing—essential for satisfying the QCD momentum sum rule. These developments connect naturally to the broader physics of generalised parton distributions and impact-parameter densities, where off-forward Compton amplitudes provide a new handle on power corrections and spatial structure. I will conclude with a recent breakthrough: the extraction of twist-3 matrix elements encoding the transverse colour-Lorentz force acting on a struck quark in deep inelastic scattering. This force, reaching magnitudes comparable to the weight of ten elephants, offers a striking new perspective on confinement at the subnucleonic scale.
