Gauge/Gravity Duality and Hadron Physics at the Light-Front

TL;DR

This paper explores light-front holography in AdS space with a positive dilaton background, improving the modeling of hadron spectra and form factors by incorporating twist-scaling dimensions and clarifying angular momentum assignments.

Contribution

It demonstrates that a positive-sign dilaton background better models hadronic phenomenology and emphasizes the importance of twist-scaling dimensions and angular momentum in AdS/QCD correspondence.

Findings

Positive dilaton background improves hadron spectrum modeling

Twist-scaling dimensions are essential for accurate form factors

Explicit connection between AdS modes and hadron internal structure

Abstract

We discuss some remarkable features of the light-front holographic mapping of classical gravity in anti-de Sitter space modified by a confining dilaton background. In particular, we show that a positive-sign dilaton solution $\exp(+\kappa^2 z^2)$ has better chances to describe the correct hadronic phenomenology than the negative solution $\exp{(- \kappa^2 z^2)}$ extensively studied in the literature. We also show that the use of twist-scaling dimensions, instead of canonical dimensions, is required to give a good description of the spectrum and form factors of hadrons. Another key element is the explicit connection of AdS modes of total angular momentum $J$ with the internal structure of hadrons and the proper identification of the orbital angular momentum of the constituents.