Glueballs and Their Kaluza-Klein Cousins

TL;DR

This paper investigates the relationship between Kaluza-Klein states and glueballs in non-supersymmetric Yang-Mills theories using string theory dualities, finding that decoupling of extra states is not clear at leading order.

Contribution

It analyzes the mass spectra of Kaluza-Klein states and glueballs in the supergravity limit, showing their masses are comparable and corrections do not ensure decoupling.

Findings

Kaluza-Klein states have masses similar to glueballs in the supergravity limit.

Leading order corrections do not cause Kaluza-Klein states to decouple.

Decoupling of Kaluza-Klein states remains unclear at this order.

Abstract

Spectra of glueball masses in non-supersymmetric Yang-Mills theory in three and four dimensions have recently been computed using the conjectured duality between superstring theory and large N gauge theory. The Kaluza-Klein states of supergravity do not correspond to any states in the Yang-Mills theory and therefore should decouple in the continuum limit. On the other hand, in the supergravity limit g_{YM}^2 N -> \infty, we find that the masses of the Kaluza-Klein states are comparable to those of the glueballs. We also show that the leading (g_{YM}^2N)^{-1} corrections do not make these states heavier than the glueballs. Therefore, the decoupling of the Kaluza-Klein states is not evident to this order.