More Anomalies from Fractional Branes

TL;DR

The paper addresses the problem of extracting UV anomalies for non-conformal supersymmetric gauge theories from gravity duals by studying explicit fractional brane solutions on orbifolds. It employs Type IIB supergravity backgrounds for fractional D3 branes on Z2 and Z2xZ2 orbifolds to map bulk fields to the four-dimensional gauge coupling through a holomorphic coupling tau_YM, and demonstrates that the resulting beta-functions and chiral anomalies match field theory expectations for both N=2 and N=1 theories. In the N=2 case, tau_YM is captured by tau_YM = i * (2M-N)/(2 pi) * log(z / rho_e), yielding the one-loop beta function beta(g) and U(1)_R anomaly; in the N=1 case, the analysis extends to all four gauge factors with appropriate beta-functions and anomaly structures, including the pure N=1 YM limit. The approach provides a direct holographic derivation of UV anomaly data from gravity, emphasizes the role of twisted bulk fields, and hints at possible IR insights via orbifold deformations.

Abstract

In this note we show how the anomalies of both pure and matter coupled N=1,2 supersymmetric gauge theories describing the low energy dynamics of fractional branes on orbifolds can be derived from supergravity.