PARAMETERIZING AND MEASURING DARK ENERGY TRAJECTORIES FROM LATE INFLATONS
Bibliographic record
Abstract
Bulk dark energy (DE) properties are determined by the redshift evolution of its pressure-to-density ratio, w de ( z ). An experimental goal is to decide if the DE is dynamical, as in the quintessence (and phantom) models treated here. We show that a three-parameter approximation w de ( z ; ε s , ε ϕ ∞ , ζ s ) fits well the ensemble of trajectories for a wide class of late-inflaton potentials V (ϕ). Markov Chain Monte Carlo probability calculations are used to confront our w de ( z ) trajectories with current observational information on Type Ia supernova, cosmic microwave background, galaxy power spectra, weak lensing, and the Lyα forest. We find that the best-constrained parameter is a low-redshift slope parameter, ε s ∝ (∂ln V /∂ϕ) 2 when the DE and matter have equal energy densities. A tracking parameter ε ϕ ∞ defining the high-redshift attractor of 1 + w de is marginally constrained. ζ s is poorly determined, which characterizes the evolution of ε s , and is a measure of ∂ 2 ln V /∂ϕ 2 . The constraints we find already rule out some popular quintessence and phantom models, or restrict their potential parameters. We also forecast how the next generation of cosmological observations improve the constraints: by a factor of about five on ε s and ε ϕ ∞ , but with ζ s remaining unconstrained (unless the true model significantly deviates from ΛCDM). Thus, potential reconstruction beyond an overall height and a gradient is not feasible for the large space of late-inflaton models considered here.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".