Effective Field Theory and Unification in AdS Backgrounds

TL;DR

This paper extends previous work on gauge coupling evolution in AdS_5 backgrounds, showing how one-loop effects of massive scalars influence low-energy couplings and how these effects can be understood via effective field theory and AdS/CFT duality.

Contribution

It provides a systematic calculation of one-loop scalar effects on gauge couplings in AdS backgrounds and demonstrates the consistency of these results with effective field theory and AdS/CFT methods.

Findings

Scalar bulk mass scales enter logarithmically in gauge coupling corrections.

Large logarithms can be derived from effective field theory running.

Scalar boundary conditions affect gauge coupling running.

Abstract

This work is an extension of our previous work, hep-th/0204160, which showed how to systematically calculate the high energy evolution of gauge couplings in compact AdS_5 backgrounds. We first directly compute the one-loop effects of massive charged scalar fields on the low energy couplings of a gauge theory propagating in the AdS background. It is found that scalar bulk mass scales (which generically are of order the Planck scale) enter only logarithmically in the corrections to the tree-level gauge couplings. As we pointed out previously, we show that the large logarithms that appear in the AdS one-loop calculation can be obtained within the confines of an effective field theory, by running the Planck brane correlator from a high UV matching scale down to the TeV scale. This result exactly reproduces our previous calculation, which was based on AdS/CFT duality. We also calculate the effects of scalar fields satisfying non-trivial boundary conditions (relevant for orbifold breaking of bulk symmetries) on the running of gauge couplings.