SciPost Submission Page
Massive holographic QFTs in de Sitter
by José Manuel Penín, Kostas Skenderis, Benjamin Withers
This Submission thread is now published as
|Authors (as Contributors):||Kostas Skenderis · Benjamin Withers|
|Date submitted:||2022-04-04 12:11|
|Submitted by:||Withers, Benjamin|
|Submitted to:||SciPost Physics|
We study strongly coupled mass-deformed-CFT on a fixed de Sitter spacetime in three dimensions via holography. We elucidate the global causal structure of the four-dimensional spacetime dual to the de Sitter invariant vacuum state. The conformal boundaries of de Sitter appear as spacelike defects sourced by the mass deformation, which extend into the bulk as curvature singularities in AdS. We compute all one- and two-point functions of the deformed-CFT stress tensor and a scalar operator order-by-order in the mass deformation for a simple holographic model. These correlation functions admit a spectral representation as a sum of simple poles corresponding to normalisable modes in the bulk.
Published as SciPost Phys. 12, 182 (2022)
Author comments upon resubmission
We thank the referee for their comments and for their suggestion. We agree that the details of the two-point function with m corrections shed further light on the stability issue. We have added some clarifying comments in section 7 paragraph 4. In particular, the strong coupling result at m=0 is stable and controlled by a CFT. The m corrections are indeed compatible with stability. This can be seen by e.g. looking at the Bessel functions which decay with a power law in conformal time governed by the index. Thus all the poles we have in the paper give rise to decaying modes and no instabilities are observed.
Response to Anonymous Report 2
We thank the referee for their comments and suggestions. Regarding the relation to hydrodynamics we have added some clarifying remarks to section 7 paragraph 5 and added a new paragraph 6. The connection to the temperature seen by a static patch observer is interesting, though this is not an avenue we have explored in this work, where we have mostly been concerned with one- and two-point functions computed in the inflationary patch. It would be interesting to understand the normalisable modes from the static patch perspective and the relation to the cosmological horizon temperature in future work. Finally, we chose to work in three dimensions because the analysis is the simplest in this case and the construction of  was already available. We are not aware of any obstructions to carrying out the analogous construction in higher dimensions. We are pursuing this for future work where indeed we hope to make contact with cosmological observations.
List of changes
- Added clarifying comments surrounding m corrections to pole locations and the stability of the theory, section 7 paragraph 4.
- Added further comments and additional discussion regarding the lack of a hydrodynamic interpretation. Section 7 paragraph 5 and added a new paragraph 6.
Submission & Refereeing History
You are currently on this page
Reports on this Submission
Anonymous Report 2 on 2022-5-4 (Invited Report)
1- Clear Presentation of Analytic Computations.
2- Well defined problem and results on the correlation functions.
The authors have clarified the points raised. This version of the manuscript is suitable for publication in SciPost.
Anonymous Report 1 on 2022-4-13 (Invited Report)
1- Clear and explicit exposition.
2- Discusses QFT on de Sitter at strong coupling.
3- Finds interesting results for the correlation function.
This paper meets all the criteria for publication in SciPost.