Glueball Spectra of SQCD-like Theories

TL;DR

This paper investigates the scalar glueball spectrum in SQCD-like theories using supergravity duals, revealing how the lightest scalar mass varies with flavor number and demonstrating Seiberg duality in the effective model.

Contribution

It introduces a five-dimensional non-linear sigma model capturing the glueball spectra and shows its invariance under Seiberg duality, providing new insights into gauge/gravity correspondence.

Findings

Lightest scalar glueball mass increases with flavor number up to Nf=2Nc

Beyond Nf=2Nc, the scalar mass decreases with more flavors

The 5D sigma model respects Seiberg duality symmetry

Abstract

We study the spectrum of scalar glueballs in SQCD-like theories whose gravity description is in terms of Nc D5 color branes wrapped on an S^2 inside a CY3-fold, and Nf backreacting D5 flavor branes wrapped on a non-compact two-cycle inside the same CY3-fold. We show that there exists a consistent truncation of the ten-dimensional Type IIB supergravity system to a five-dimensional non-linear sigma model consisting of four scalars coupled to gravity. Studying fluctuations of the scalars as well as the metric around particular backgrounds allows us to compute their spectra. A few different backgrounds share the same qualitative features, namely that the mass of the lightest scalar glueball increases as the number of flavors is increased, until one reaches the point Nf = 2 Nc after which the opposite behaviour is obtained. We show that the five-dimensional non-linear sigma model obeys Seiberg duality, and demonstrate this explicitly for the spectra of a class of backgrounds that are Seiberg dual to themselves.