Holographic QCD running coupling constant from the Ricci flow
Héctor Cancio (Grup de Física Teòrica, Departament de Física, Universitat Autònoma de Barcelona and Institut de Física d’Altes Energies (IFAE), 08193 Bellaterra (Barcelona), Spain); Pere Masjuan (Institut de Física d’Altes Energies (IFAE) and The Barcelona Institute of Science and Technology (BIST), Campus UAB, 08193 Bellaterra (Barcelona), Spain, Grup de Física Teòrica, Departament de Física, Universitat Autònoma de Barcelona and Institut de Física d’Altes Energies (IFAE), 08193 Bellaterra (Barcelona), Spain)
Through a holographic model of QCD, we present a phenomenological approach to study the running of the strong coupling constant in both nonperturbative and perturbative regimes. The renormalization of the metric tensor, driven by the Ricci Flow, and the breaking of conformal and chiral symmetries—thanks to introducing a double dilaton model and large- corrections—allows us to relate the existence of an infrared fixed point in the coupling constant with a smooth matching to perturbative QCD well above 2 GeV. This is done through a model with two fit parameters and one matching point. The proposed dilaton model yields linear Regge trajectories and decay constants for scalar, vector, and tensor meson families similar to their experimental counterparts.