Observable detail · ATOM
Neutron lifetime \(\tau_n\) (UCN vs beam)
| Prediction / mechanism | \(\tau_n \sim 880\) s; UCN-vs-beam \(\sim 4\sigma\) discrepancy is not addressed by DCT. |
|---|---|
| Measured | PDG 2024 \(\tau_n^{\rm UCN} = 877.75 \pm 0.28\) s vs \(\tau_n^{\rm beam} = 887.7 \pm 1.2\) s. |
| Residual / status | NEUTRAL — not a DCT-specific test |
| Status | SOFT |
| Source paper | DCT-SM-01 |
Mechanism
DCT inherits the SM \(\beta\)-decay rate; the UCN-vs-beam discrepancy lies in the SM systematics.
Derivation
The derivation chain follows the cluster paper DCT-SM-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
| Domain | Atomic / precision QED (ATOM) |
|---|---|
| Input data source | See "References" below for the canonical public-archive citation. |
| Measurement procedure | The measured value used here is the most recent peer-reviewed central value plus 1σ uncertainty from the cited reference. |
| Acceptance threshold | HIT: residual within 1σ of measurement. SOFT: directional agreement within bracketing range. OPEN: untested or unresolved. |
| Falsification threshold | MISS: prediction excluded at ≥3σ by the canonical measurement under the corpus-canonical (constant-\(P_0\)) treatment. |
| Current status | See verdict pill above. |
Python verification
Verification script: particle_physics_tests.py. Run with python3 particle_physics_tests.py to reproduce the canonical DCT result against the public-archive measurement source listed below.
Cross-references
Related observables: neutron-interferometry · n-p-mass-split.
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-SM-01) is the canonical source of the derivation chain.
References
- PDG 2024 — Neutron lifetime
- Source paper: DCT-SM-01
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