Any unified early and late dark energy scenario with a single tracking scalar field requires a potential with three distinct slopes arranged in a steep-steeper-shallow hierarchy.
Canonical reference
Review of Hubble tension solutions with new SH0ES and SPT-3G data
Canonical reference. 83% of citing Pith papers cite this work as background.
abstract
We present an updated analysis of eleven cosmological models that may help reduce the Hubble tension, which now reaches the $6\sigma$ level when considering the latest SH0ES measurement versus recent CMB and BAO data, assuming $\Lambda$CDM. Specifically, we look at five classical extensions of $\Lambda$CDM (with massive neutrinos, spatial curvature, free-streaming or self-interacting relativistic relics, or dynamical dark energy) and six elaborate models featuring either a time-varying electron mass, early dark energy or some non-trivial interactions in the neutrino sector triggered by a light Majoron. We improve over previous works in several ways. We include the latest data from the South Pole Telescope as well as the most recent measurement of the Hubble rate by the SH0ES collaboration. We treat the summed neutrino mass as a free parameter in most of our models, which reveals interesting degeneracies and constraints. We define additional metrics to assess the potential of a model to reduce or even solve the Hubble tension. We validate an emulator that uses active learning to train itself during each parameter inference run for any arbitrary model. We find that the time-varying electron mass and the Majoron models are now ruled out at more than $3\sigma$. Models with a time-varying electron mass and spatial curvature or with early dark energy reduce the tension to $1.0-2.9\sigma$. Nevertheless, none of the models considered in this work is favored with enough statistical significance to become the next concordance model of Cosmology.
citation-role summary
citation-polarity summary
years
2026 10representative citing papers
For fixed sound-horizon and supernova calibrations, no late-time modification—even one violating cosmic distance duality—can resolve the Hubble tension, because the required ~8-10% CDDR violation is excluded by BAO, cosmic-chronometer, and CMB spectral constraints.
Two-field axion-like early dark energy reduces Hubble tension to 1.5 sigma residual and improves high-ell CMB fits over single-field models.
Node-based reconstruction of cosmic expansion prefers stronger deceleration at z≈1.7 than smooth DE EoS parametrizations, isolating z~1.5-2 as a window where the latter may compress localized kinematic features permitted by current data.
Constraints on temperature-dependent CPT-violating electron-positron mass asymmetry b0(T) = α T² from BBN abundances of 4He, D, and Neff give α ≳ 10^{-6} GeV^{-1} for keV-scale effects at BBN.
A swampland-inspired DM-EDE coupling is tested against DESI DR2 BAO data, showing the EDE potential construction affects late-time dark energy constraints.
The Zel'dovich smearing approximation for model-agnostic BAO inference is extended to include fiducial cosmology distortions and validated on AbacusSummit simulations of DESI- and Euclid-like samples, producing unbiased constraints.
Pure early or late fixes to the Hubble tension are tightly constrained; remaining options are combined early-late interacting dark energy or new physics at the local-to-homogeneous transition.
MCMC constraints on two Lambda(t) models with DESI DR2, CC, and Pantheon+ data yield H0 ~72.5-73 km/s/Mpc, Omega_m0 near standard values in joint fits, and n~0.3 indicating mild deviation from LambdaCDM.
citing papers explorer
-
Unifying Early and Late Dark Energy: Dynamical Requirements and Obstructions
Any unified early and late dark energy scenario with a single tracking scalar field requires a potential with three distinct slopes arranged in a steep-steeper-shallow hierarchy.
-
Can Distance Duality Violation Save Late-time Solutions to the Hubble Tension?
For fixed sound-horizon and supernova calibrations, no late-time modification—even one violating cosmic distance duality—can resolve the Hubble tension, because the required ~8-10% CDDR violation is excluded by BAO, cosmic-chronometer, and CMB spectral constraints.
-
Double the axions, half the tension: multi-field early dark energy eases the Hubble tension
Two-field axion-like early dark energy reduces Hubble tension to 1.5 sigma residual and improves high-ell CMB fits over single-field models.
-
Do equation of state parametrizations of dark energy faithfully capture the dynamics of the late universe?
Node-based reconstruction of cosmic expansion prefers stronger deceleration at z≈1.7 than smooth DE EoS parametrizations, isolating z~1.5-2 as a window where the latter may compress localized kinematic features permitted by current data.
-
Temperature-Dependent CPT Violation: Constraints from Big Bang Nucleosynthesis
Constraints on temperature-dependent CPT-violating electron-positron mass asymmetry b0(T) = α T² from BBN abundances of 4He, D, and Neff give α ≳ 10^{-6} GeV^{-1} for keV-scale effects at BBN.
-
Imprint of swampland-inspired coupled early dark energy
A swampland-inspired DM-EDE coupling is tested against DESI DR2 BAO data, showing the EDE potential construction affects late-time dark energy constraints.
-
Impact of fiducial cosmology in model-agnostic cosmological inference with the BAO feature
The Zel'dovich smearing approximation for model-agnostic BAO inference is extended to include fiducial cosmology distortions and validated on AbacusSummit simulations of DESI- and Euclid-like samples, producing unbiased constraints.
-
The Hubble tension: A decade review
Pure early or late fixes to the Hubble tension are tightly constrained; remaining options are combined early-late interacting dark energy or new physics at the local-to-homogeneous transition.
-
Observational tests of \texorpdfstring{$\Lambda(t)$}{Lambda(t)} cosmology in light of DESI DR2
MCMC constraints on two Lambda(t) models with DESI DR2, CC, and Pantheon+ data yield H0 ~72.5-73 km/s/Mpc, Omega_m0 near standard values in joint fits, and n~0.3 indicating mild deviation from LambdaCDM.
- Probing dynamical dark energy with late-time data: Evidence, tensions, and the limits of the $w_0w_a$CDM framework