Observable detail · COS

DESI Year-1 \(w_0\), \(w_a\) posterior

Prediction / mechanismPredicted \(w_0 = -1\), \(|w_a| < 10^{-4}\); DESI Y1 hint of \(w_a \ne 0\) is a forward discriminator. DESI Y3 will adjudicate.
MeasuredDESI Year-1 cosmology release (2024); Year-3 release expected 2026.
Residual / statusOPEN / FORWARD; DESI Y3 will discriminate at \(\Delta w_a \sim 10^{-3}\)
StatusOPEN
Source paperDCT-COS-01

Mechanism

Same background-EOS prediction as Pantheon+. Any \(|w_a| \gtrsim 10^{-4}\) detection would falsify the canonical late-time vacuum.

Derivation

The derivation chain follows the cluster paper DCT-COS-01 and reduces to the canonical DCT constants (\(P_0 = 0.851\), \(\omega_0 = 50{,}037\), \(c_{BD} = 138{,}189\), master identity \(2\omega_0 + 3 = c_{BD} \cdot P_0^2 = 100{,}077\)). See the cluster paper for the full multi-line derivation.

Methodology

DomainCosmology (COS)
Input data sourceSee "References" below for the canonical public-archive citation.
Measurement procedureThe measured value used here is the most recent peer-reviewed central value plus 1σ uncertainty from the cited reference.
Acceptance thresholdHIT: residual within 1σ of measurement. SOFT: directional agreement within bracketing range. OPEN: untested or unresolved.
Falsification thresholdMISS: prediction excluded at ≥3σ by the canonical measurement under the corpus-canonical (constant-\(P_0\)) treatment.
Current statusSee verdict pill above.

Python verification

Verification script: pantheon_supernova_analysis.py. Run with python3 pantheon_supernova_analysis.py to reproduce the canonical DCT result against the public-archive measurement source listed below.

Cross-references

Related observables: w-0 · w-a · pantheon-w0-wa · desi-y3-bao.

Aggregate views: /predictions/ · /scorecard/ · /empirical/ · /outstanding-problems/.

Audit notes

This sub-page is part of the post-build-out of the observable archive (see the observable index). Verdict reflects the corpus-canonical (constant-\(P_0\)) treatment. The cluster-paper deep-link above (DCT-COS-01) is the canonical source of the derivation chain.

References

Back to all observables or the predictions table.