Origin of the nucleon gravitational form factor $B_N(t)$: Exposition in light-front holographic QCD

Abstract

Recent lattice QCD simulations and phenomenological models indicate that the nucleon's gravitational form factor $B_N(t)$ remains remarkably small at finite momentum transfer $t$. While $B_N(0)=0$ is a known consequence of the equivalence principle, the physical origin of its suppression at finite $t$ has not been fully elucidated. In this work, we demonstrate that the smallness of $B_N(t)$ arises from a fundamental cancellation within the nucleon's wave functions. Using light-front holographic QCD, we show that $B_N(t)$ is governed by an antisymmetric factor in the longitudinal dynamics that leads to the exact vanishing of the form factor in the symmetric limit and significant suppression for realistic nucleon structures. Our results suggest that the smallness of $B_N(t)$ is a signature of the nucleon's dominant S-wave character, providing a formal justification for its frequent omission in practical applications like near-threshold $J/\psi$ production.

7 pages, 4 figures. To appear in Phys. Rev. D as a letter

References in corpus (17)

• Nucleon electromagnetic and gravitational form factors from holography
• Nucleon form-factors of the energy momentum tensor in the chiral quark-soliton model
• Baryon Spectrum from Superconformal Quantum Mechanics and its Light-Front Holographic Embedding
• Superconformal Baryon-Meson Symmetry and Light-Front Holographic QCD
• The nucleon form-factors of the energy momentum tensor in the Skyrme model
• QCD Analysis of Near-Threshold Photon-Proton Production of Heavy Quarkonium
• Gravitational form factors of the proton from lattice QCD
• The pion mass dependence of the nucleon form-factors of the energy momentum tensor in the chiral quark-soliton model
• Energy momentum tensor and the D-term in the bag model
• Gravitational form factors within light-cone sum rules at leading order
• Nucleon D-term in holographic QCD
• Gravitational form factors and angular momentum densities in light-front quark-diquark model
• Gravitational form factors of pion from top-down holographic QCD
• Dispersive Determination of Nucleon Gravitational Form Factors
• Deuteron gravitational form factors, generalized parton distributions, and charge density in the framework of the soft-wall AdS/QCD model
• Gravitational form factors of pions, kaons and nucleons from dispersion relations
• Scalar-glueball-mediated scale-anomaly dominance of the confining pressure of the pion in holographic QCD