Evaluation Of Glueball Masses From Supergravity

TL;DR

This paper investigates the eigenvalue problem for glueball masses using supergravity duality, providing analytic solutions and numerical results, and discusses boundary conditions crucial for the mass spectrum in a non-supersymmetric QCD context.

Contribution

It offers a detailed analysis of boundary conditions and constructs explicit wave function expansions for glueball mass calculations in supergravity models.

Findings

Mass eigenvalues up to m^2=1000 are computed.

Smoothness and normalizability conditions restrict possible solutions.

No solutions with vanishing derivative at the horizon are found.

Abstract

In the framework of the conjectured duality relation between large $N$ gauge theory and supergravity the spectra of masses in large $N$ gauge theory can be determined by solving certain eigenvalue problems in supergravity. In this paper we study the eigenmass problem given by Witten as a possible approximation for masses in QCD without supersymmetry. We place a particular emphasis on the treatment of the horizon and related boundary conditions. We construct exact expressions for the analytic expansions of the wave functions both at the horizon and at infinity and show that requiring smoothness at the horizon and normalizability gives a well defined eigenvalue problem. We show for example that there are no smooth solutions with vanishing derivative at the horizon. The mass eigenvalues up to $m^{2}=1000$ corresponding to smooth normalizable wave functions are presented. We comment on the relation of our work with the results found in a recent paper by Cs\'aki et al., hep-th/9806021, which addresses the same problem.