Proton Structure from a Soft-Wall Holographic QCD Model: Mass Spectrum, Form Factors, and Mechanical Properties

Abstract

Understanding the internal structure of the proton-including its mass spectrum, electromagnetic and gravitational form factors, and mechanical properties-remains a central challenge in hadronic physics. While lattice QCD and experimental measurements provide valuable insights, a holographic framework with a single parameter set capable of simultaneously describing these diverse observables is still lacking. Here, we employ the soft wall model, a phenomenological holographic approach that incorporates gluon condensation and linear confinement, to compute the proton mass spectrum, electromagnetic form factors (EMFFs), and gravitational form factors (GFFs). Our results show good agreement with recent experimental data and lattice QCD calculations. Despite its phenomenological nature, the model's ability to simultaneously describe multiple observables suggests that it effectively mimics some key QCD features.