V2.356 - Neutrino Mass Constraints from Lambda
V2.356: Neutrino Mass Constraints from Lambda
Question
The framework fixes Omega_Lambda with zero parameters. Combined with Planck CMB data and neutrino oscillation measurements, what does this imply for:
- Normal vs inverted mass hierarchy?
- The neutrino mass sum Sigma_m_nu?
- Majorana vs Dirac nature?
- Which upcoming experiments can test these predictions?
The Chain of Connected Predictions
delta_total = -149/12 (SM trace anomaly + graviton)
↓
Omega_Lambda = 149√π/384 = 0.6877 (zero free parameters)
↓
N_nu = 3, Majorana (required for consistency at 2.9σ over Dirac)
↓
H_0 = 67.46 km/s/Mpc (from Planck Omega_m*h^2)
↓
Sigma_m_nu < 0.12 eV (consistent with Planck+BAO)
↓
0νββ must be observed (if Majorana, |m_ββ| > 1 meV)
No other framework connects the cosmological constant to neutrino physics. In LCDM, Omega_Lambda and neutrino properties are independent parameters.
Key Results
1. Majorana vs Dirac: 2.9σ Separation
| Type | N_eff | delta_total | R | Tension | Status |
|---|---|---|---|---|---|
| Majorana | 128 | -149/12 | 0.6877 | +0.42σ | Preferred |
| Dirac | 134 | -12.600 | 0.6667 | -2.47σ | Disfavored |
The Majorana-Dirac separation is 2.89σ from Planck data alone. Adding 3 right-handed neutrinos (Dirac) shifts R from 0.688 to 0.667 — a 3% effect that crosses the 2σ threshold.
The framework predicts Majorana neutrinos. This is testable by neutrinoless double beta decay experiments (nEXO, LEGEND-1000) within 5 years.
2. Hierarchy Preference: None (0.37σ)
| Hierarchy | Σm_ν (min) | Ω_CDM·h² | Tension with Planck |
|---|---|---|---|
| Normal | 58.2 meV | 0.12001 | +0.00σ |
| Inverted | 100.0 meV | 0.11956 | -0.37σ |
The framework does NOT distinguish hierarchies. The 42 meV difference in minimum mass shifts Ω_CDM by only 0.1% — far below CMB sensitivity. Both hierarchies are equally consistent with Ω_Λ = 0.6858.
JUNO (2025, reactor oscillations) and DUNE (2028, long-baseline) will determine the hierarchy independently.
3. Cosmological Parameters
| Parameter | Framework (1-loop) | Planck LCDM | Difference |
|---|---|---|---|
| Ω_Λ | 0.6858 | 0.6847 | +0.0011 |
| H₀ (km/s/Mpc) | 67.46 | 67.35 | +0.11 |
| Ω_m | 0.3142 | 0.3153 | -0.0011 |
| Ω_CDM (NH) | 0.2637 | 0.2647 | -0.0010 |
The framework shifts H₀ by +0.11 km/s/Mpc (+0.2σ) relative to Planck LCDM. This is in the SAME direction as the Hubble tension — the framework predicts a slightly larger H₀ than Planck LCDM, but far from resolving the tension with SH0ES.
4. Experimental Landscape (2025-2030)
| Experiment | Year | Tests | Framework prediction |
|---|---|---|---|
| JUNO | 2025 | Hierarchy at 3σ | Both OK |
| DUNE | 2028 | Hierarchy + CP at 5σ | Both OK |
| LEGEND-1000 | 2029 | 0νββ (Majorana) | Must observe |
| nEXO | 2030 | 0νββ (Majorana) | Must observe |
| CMB-S4 | 2029 | Σm_ν to 15 meV | < 0.12 eV |
| Euclid + DESI | 2030 | Σm_ν to 20 meV | < 0.12 eV |
| Project 8 | 2030 | m_β to 40 meV | Consistent |
The critical test: nEXO/LEGEND-1000 will cover the full inverted hierarchy band for 0νββ. If NO signal is seen, either neutrinos are Dirac (disfavoring the framework at 2.9σ) or the hierarchy is normal with very small m₁.
What This Means for the Science
Unique to This Framework
-
Lambda determines neutrino nature: Majorana preferred at 2.9σ because Dirac neutrinos add 6 Weyl DOFs, pushing R below the observed Ω_Λ.
-
The prediction chain is unfakeable: delta_total → Ω_Λ → N_ν → Majorana is a 4-step logical chain. Each step is testable independently.
-
Experimental timeline is concrete: LEGEND-1000 (2029) and nEXO (2030) will test the Majorana prediction. CMB-S4 will measure Σm_ν.
Honest Assessment
Strength: The Majorana-Dirac separation (2.9σ) is the framework’s strongest prediction beyond Ω_Λ itself. It connects particle physics (neutrino nature) to cosmology (dark energy) through a specific, testable chain.
Weakness: The framework does NOT predict the neutrino mass hierarchy, the absolute mass scale, or CP violation phase. These require physics beyond the trace anomaly (e.g., flavor structure). The framework’s neutrino predictions are limited to COUNTING (N_ν = 3) and TYPE (Majorana).
Falsification: If Dirac neutrinos are confirmed AND the framework’s Ω_Λ prediction remains correct, the framework would need modification to accommodate 6 extra Weyl DOFs while maintaining R ≈ 0.685.
Files
src/neutrino_mass.py: Core calculation module (oscillation data, cosmological chain)tests/test_neutrino_mass.py: 13 tests, all passingresults.json: Full numerical output