A note on gravity-scalar fluctuations in holographic RG flow geometries

TL;DR

This paper develops a method to analyze scalar and graviton fluctuations in five-dimensional holographic models with scalar fields, enabling computation of two-point functions in non-conformal boundary theories.

Contribution

It introduces a decoupling procedure for graviton and scalar fluctuations in holographic RG flow geometries, simplifying the calculation of correlation functions.

Findings

Successfully decoupled scalar fluctuations from graviton modes.

Computed two-point functions for specific RG flow backgrounds.

Obtained physically reasonable correlation functions.

Abstract

We study five-dimensional gravity models with non-vanishing background scalar fields which are dual to non-conformal boundary field theories. We develop a procedure to decouple the graviton fluctuations from the scalar ones and apply it to the simplest case of one scalar field. The quadratic action for the decoupled scalar fluctuations has a very simple form and can be used to compute two-point functions. We perform this computation for the two examples of background RG flow recently considered by DeWolfe and Freedman and find physically reasonable results.