Longitudinal dynamics in light-front holographic QCD and hadron spectroscopy

We demonstrate that the ’t Hooft equation and the light-front holographic Schrodinger equation are complementary to each other in governing ¨ the longitudinal and the transverse dynamics of color confinement in mesons (quark-antiquark) and baryons (quark-diquark). Together, they describe remarkably well the spectroscopic data for the light-light, heavy-light and heavy-heavy hadrons. In all hadrons, the transverse dynamics of confinement is controlled by the universal emerging hadronic scale of the light-front holography, κ ∼ 0.5 GeV, which, in heavy-heavy hadrons, coincides with the ’t Hooft coupling that governs the longitudinal confinement. This reflects the restoration of the rotational symmetry in the non-relativistic limit.