Correlation Functions in Holographic RG Flows
Ioannis Papadimitriou, Kostas Skenderis
TL;DR
The paper advances holographic renormalization by adopting a Hamiltonian framework that treats the radial coordinate as time, enabling renormalized correlators to be obtained from linearized fluctuations and only the relevant counterterm contributions. This method makes Ward identities and anomalies manifest while avoiding a full near-boundary analysis, significantly reducing computational effort across RG-flow backgrounds. It applies to both flat Poincaré domain walls and AdS-sliced walls, and includes a detailed treatment of the Janus solution, where vevs and wall-conformal two-point functions are shown to satisfy defect conformal symmetry. The results provide a consistent, efficient toolkit for computing n-point functions in holographic RG flows and offer a path to exploring non-AdS geometries and defect field theories.
Abstract
We discuss the computation of correlation functions in holographic RG flows. The method utilizes a recently developed Hamiltonian version of holographic renormalization and it is more efficient than previous methods. A significant simplification concerns the treatment of infinities: instead of performing a general analysis of counterterms, we develop a method where only the contribution of counterterms to any given correlator needs to be computed. For instance, the computation of renormalized 2-point functions requires only an analysis at the linearized level. We illustrate the method by discussing flat and AdS-sliced domain walls. In particular, we discuss correlation functions of the Janus solution, a recently discovered non-supersymmetric but stable AdS-sliced domain wall.
