A Rational Target for Dynamical Dark Energy: w0=-27/28, wa=-1/28

Abstract

A registered dark-energy branch, preserved as a public record of a prediction that has since been retired under its own rules — the discipline of pre-registration requires failed predictions to stay visible. In the Chevallier–Polarski–Linder parameterisation w(a) = w₀ + wₐ(1−a) the framework had fixed a single rational point, w₀ = −27/28 ≈ −0.964, wₐ = −1/28 (equivalently the one-line law w(a) = −1 + a/28): a mild, non-phantom thawing-like departure from ΛCDM produced not by a fit to DESI, Euclid, Planck, or supernova data but by the same 28-channel service clock that sets the scalar tilt n_s = 27/28. The dated outcome is now recorded: this specific late-time branch is internally killed by the pinned-H₀/acoustic-clock consistency test and kept only as a frozen reopen condition — the framework no longer treats the CPL point as its active dark-energy prediction unless the explicitly stated reopen condition is met. Late-time surveys may still test the frozen point, but the branch failed internally before the external posterior became decisive: an honest negative, retained rather than refitted.

Keywords

How to cite

Elliman, D. (2026). A Rational Target for Dynamical Dark Energy: w0=-27/28, wa=-1/28. Neuro-Symbolic Ltd technical report. https://doi.org/10.5281/zenodo.21251745

@techreport{elliman2026darkenergyprediction,
  author      = {Elliman, David},
  title       = {A Rational Target for Dynamical Dark Energy: w0=-27/28, wa=-1/28},
  institution = {Neuro-Symbolic Ltd},
  year        = {2026},
  doi         = {10.5281/zenodo.21251745},
  url         = {https://neusym.ai/papers/dark_energy_prediction/}
}