Graviton correlator and metric perturbations in de Sitter brane-world

TL;DR

This paper studies metric perturbations and graviton correlators in a de Sitter brane-world model inspired by dS/CFT correspondence, revealing stronger short-distance correlations and quantum CFT effects.

Contribution

It explicitly derives the 4d effective action and graviton correlator in a de Sitter brane-world, incorporating holographic RG and quantum CFT contributions.

Findings

Short distance graviton correlator is significantly stronger than in General Relativity.

Quantum brane CFT dominates the graviton correlator on small scales.

Induced cosmological and Newton constants are explicitly calculated.

Abstract

We consider de Sitter brane-world motivated by dS/CFT correspondence where both bulk and brane are de Sitter spaces. The brane tension is fixed by holographic RG. The 4d effective action for metric perturbations and 4d graviton correlator are explicitly found. The induced values of cosmological and Newton constants are calculated. The short distance behaviour of the graviton correlator (when no brane matter presents) turns out to be significally stronger than in the case of General Relativity. It is shown that quantum brane CFT gives the dominant contribution to graviton correlator on small scales like in Brane New World scenario.