Spin-Two Glueballs, Positive Energy Theorems and the AdS/CFT Correspondence

TL;DR

This paper calculates the spectrum of spin-two glueballs in dual field theories using AdS/CFT, finds spectral degeneracies, and extends positive energy theorems to higher dimensions.

Contribution

It provides an exact spectrum of graviton excitations in AdS soliton backgrounds and generalizes positive energy theorems beyond three dimensions.

Findings

Degeneracy of tensor and scalar spectra across dimensions

Spectrum matches spin-two glueballs in dual QCD theories

Positive energy conjecture extended to arbitrary dimensions

Abstract

We determine the spectrum of graviton excitations in the background geometry of the AdS soliton in p+2 dimensions. Via the AdS/CFT correspondence this corresponds to determining the spectrum of spin two excitations in the dual effective p-dimensional field theories For the cases of D3- and M5-branes these are the spin two glueballs of QCD_3 and QCD_4 respectively. For all values of p we find an exact degeneracy of the spectra of these tensor states and certain scalar excitations. Our results also extend the perturbative proof of a positive energy conjecture for asymptotically locally AdS spacetimes (originally proposed for p=3) to an arbritrary number of dimensions.