Glueball Spectrum for QCD from AdS Supergravity Duality

TL;DR

This paper analyzes the complete glueball spectrum of QCD using AdS supergravity duality, revealing patterns similar to lattice QCD results despite strong coupling limitations.

Contribution

It provides a detailed calculation of the glueball spectrum from AdS supergravity, including spectral splitting and degeneracy patterns for QCD in strong coupling.

Findings

Spectral splitting and degeneracy patterns resemble lattice QCD results.

Identifies glueball states with specific quantum numbers from supergravity equations.

Mass inequalities and spin-parity patterns align with known QCD spectra.

Abstract

We present the analysis of the complete glueball spectrum for the $AdS^7$ black hole supergravity dual of $QCD_4$ in strong coupling limit: $g^2 N \to \infty$. The bosonic fields in the supergravity multiplet lead to 6 independent wave equations contributing to glueball states with $J^{PC} = 2^{++},1^{+-}, 1^{--}$, $0^{++}$ and $0^{-+}$. We study the spectral splitting and degeneracy patterns for both $QCD_4$ and $QCD_3$. Despite the expected limitations of a leading order strong coupling approximation, the pattern of spins, parities and mass inequalities bear a striking resemblance to the known $QCD_4$ glueball spectrum as determined by lattice simulations at weak coupling.