Hilltop Quintessence
read the original abstract
We examine hilltop quintessence models, in which the scalar field is rolling near a local maximum in the potential, and w is close to -1. We first derive a general equation for the evolution of the scalar field in the limit where w is close to -1. We solve this equation for the case of hilltop quintessence to derive w as a function of the scale factor; these solutions depend on the curvature of the potential near its maximum. Our general result is in excellent agreement (delta w < 0.5%) with all of the particular cases examined. It works particularly well (delta w < 0.1%) for the pseudo-Nambu-Goldstone Boson potential. Our expression for w(a) reduces to the previously-derived slow-roll result of Sen and Scherrer in the limit where the curvature goes to zero. Except for this limiting case, w(a) is poorly fit by linear evolution in a.
This paper has not been read by Pith yet.
Forward citations
Cited by 3 Pith papers
-
Assessing observational constraints on dark energy
Quintessence models satisfying NEC everywhere predict the w0 > -1 and w0+wa < -1 sector favored by data, due to an approximate degeneracy in the w(z) = w0 + wa z/(1+z) parameterization.
-
Extended Dark Energy analysis using DESI DR2 BAO measurements
Extended analysis of DESI DR2 data confirms robust evidence for dynamical dark energy with phantom crossing preference, stable under parametric and non-parametric modeling.
-
Comparing Minimal and Non-Minimal Quintessence Models to 2025 DESI Data
Quintessence models with standard potentials give only modest improvements over Lambda to DESI data on evolving dark energy, while non-minimal couplings allow temporary phantom behavior but face tight gravity constrai...
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.