Abstract:

Protons, neutrons, pions -- in fact all hadrons and nuclei -- are bound states of confined quarks and antiquarks. In fact, an isolated quark has never been observed. The interactions between the quarks are believed to be governed by the fundamental gauge theory of quarks and gluons called quantum chromodynamics (QCD). A key question in QCD is to not only understand the fundamental interactions which underly quark confinement, but to also explain the observed dynamics and spectroscopy of hadrons and nuclei. A related challenge is to understand how the masses of the proton and other hadrons -- the masses that gives mass to all objects surrounding us -- could emerge in a theory of confined quarks which -- paradoxically -- does not have an underlying mass scale. I will present a novel approach to quark and gluon confinement and the emergence of hadronic masses in QCD. This new approach is based on a novel physics tool called ``light-front holography". This new formalism also leads to manifestations of boson-fermion supersymmetry in hadron physics -- relating the masses of mesons, baryons and a new type of hadron: ``tetraquarks" (bound states of two quarks and two antiquarks). It also helps to explain how the quark and gluon jets produced at high energy colliders convert to hadrons.