Does DESI prefer Damped Oscillating Dark Energy over Cosmological constant?
Abstract
We investigate a dark-energy equation of state governed by a damped harmonic oscillator equation, admitting underdamped, critically damped, and overdamped solutions. Confronting the model with Planck CMB distance priors, DESI BAO, BBN, cosmic chronometers, and three Type~Ia supernova compilations, we find that the data select an underdamped solution yielding H0 = 70.9 ± 1.1 km/s/Mpc with DES-Dovekie and H0 = 72.0+1.4−2.1 km/s/Mpc with Union3, without any local H0 prior. These higher values of H0 arise along the Ωm--H0 degeneracy direction while the sound horizon remains nearly unchanged at rd ≃ 145~Mpc, indicating that the enhancement of the late-time expansion rate is a geometrical effect that does not address the early-time calibration of rd. In contrast, the Pantheon+ compilation selects a near-critically damped solution with a prior-limited positive w0 and H0 = 66.23 ± 0.85 km/s/Mpc, highlighting the sensitivity of the model to the low-redshift distance information encoded in the different supernova compilations. The Bayesian evidence relative to ΛCDM is inconclusive for the DES-Dovekie and Union3 combinations, whereas Pantheon+ shows a strong preference for the damped-oscillator model, driven by the departure from w=−1 at z≲0.1.
Related
- Four-Sector Cosmology (FSC): A Complex Dark Energy Field, Spontaneous Symmetry Breaking, and the Origin of the Cosmological Constant from Observed Matter Asymmetry δ = 0.2%
- Natural Inflation with a negative cosmological constant
- Infrared Screening of the Cosmological Constant
- Running cosmological constant in light of recent CMB-BAO data
- Observational constraints on a damped harmonic oscillator model of dark energy
BibTeX
@misc{hussain2026does,
title = {{Does DESI prefer Damped Oscillating Dark Energy over Cosmological constant?}},
author = {Saddam Hussain and Simran Arora and Qiang Wu and Tao Zhu},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2606.17550},
eprint = {2606.17550},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2606.17550},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Does DESI prefer Damped Oscillating Dark Energy over Cosmological constant?
AU - Saddam Hussain
AU - Simran Arora
AU - Qiang Wu
AU - Tao Zhu
PY - 2026
DA - 2026/09/24
PB - arXiv
DO - 10.48550/arxiv.2606.17550
UR - https://arxiv.org/abs/2606.17550
AB - We investigate a dark-energy equation of state governed by a damped harmonic oscillator equation, admitting underdamped, critically damped, and overdamped solutions. Confronting the model with Planck CMB distance priors, DESI BAO, BBN, cosmic chronometers, and three Type~Ia supernova compilations, we find that the data select an underdamped solution yielding H_0 = 70.9 ± 1.1 km/s/Mpc with DES-Dovekie and H_0 = 72.0^+1.4_−2.1 km/s/Mpc with Union3, without any local H_0 prior. These higher values of H_0 arise along the Ω_m--H_0 degeneracy direction while the sound horizon remains nearly unchanged at r_d ≃ 145~Mpc, indicating that the enhancement of the late-time expansion rate is a geometrical effect that does not address the early-time calibration of r_d. In contrast, the Pantheon+ compilation selects a near-critically damped solution with a prior-limited positive w_0 and H_0 = 66.23 ± 0.85 km/s/Mpc, highlighting the sensitivity of the model to the low-redshift distance information encoded in the different supernova compilations. The Bayesian evidence relative to ΛCDM is inconclusive for the DES-Dovekie and Union3 combinations, whereas Pantheon+ shows a strong preference for the damped-oscillator model, driven by the departure from w=−1 at z≲0.1.
ER -