Kinematical and Dynamical Aspects of Higher-Spin Bound-State Equations in Holographic QCD

TL;DR

This paper develops a unified holographic framework for deriving wave equations for hadrons of arbitrary spin, linking higher-dimensional AdS space geometry to light-front Hamiltonian dynamics, and analyzing spectral features in QCD.

Contribution

It introduces a general method to derive holographic wave equations for all spins, including half-integer, from an effective higher-dimensional action, clarifying the separation of kinematics and dynamics.

Findings

Derived holographic wave equations for arbitrary spin hadrons.

Mapped higher-dimensional equations to light-front Hamiltonian.

Analyzed spectral systematics of mesons and baryons.

Abstract

In this paper we derive holographic wave equations for hadrons with arbitrary spin starting from an effective action in a higher-dimensional space asymptotic to anti-de Sitter (AdS) space. Our procedure takes advantage of the local tangent frame, and it applies to all spins, including half-integer spins. An essential element is the mapping of the higher-dimensional equations of motion to the light-front Hamiltonian, thus allowing a clear distinction between the kinematical and dynamical aspects of the holographic approach to hadron physics. Accordingly, the non-trivial geometry of pure AdS space encodes the kinematics, and the additional deformations of AdS space encode the dynamics, including confinement. It thus becomes possible to identify the features of holographic QCD which are independent of the specific mechanisms of conformal symmetry breaking. In particular, we account for some aspects of the striking similarities and differences observed in the systematics of the meson and baryon spectra.