Journal
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
Volume -, Issue 12, Pages -Publisher
IOP Publishing Ltd
DOI: 10.1088/1475-7516/2021/12/020
Keywords
modified gravity; Cosmological perturbation theory in GR and beyond
Funding
- Japan Society for the Promotion of Science (JSPS) [20K03969]
- JSPS [17H02890, 17H06359]
- World Premier International Research Center Initiative, MEXT, Japan
- JSPS KAKENHI [JP21J00695]
- Grants-in-Aid for Scientific Research [17H02890] Funding Source: KAKEN
Ask authors/readers for more resources
The study focuses on U-DHOST theories, specifically examining the extra mode that arises in a generic coordinate system. The analysis reveals that this extra mode does not propagate, satisfying a three-dimensional elliptic differential equation on a spacelike hypersurface. The study also delves into how to handle this mysterious mode at both linear and nonlinear levels.
We study U-DHOST theories, i.e., higher-order scalar-tensor theories which are degenerate only in the unitary gauge and yield an apparently unstable extra mode in a generic coordinate system. We show that the extra mode satisfies a three-dimensional elliptic differential equation on a spacelike hypersurface, and hence it does not propagate. We clarify how to treat this shadowy mode at both the linear and the nonlinear levels.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available
Share Paper
