MOND-Synchronism Comparator
MOND (Modified Newtonian Dynamics) and Synchronism both explain galaxy rotation without dark matter particles. Here's how they compare, point by point.
The Acceleration Scale a₀
MOND (Milgrom 1983)
a₀ ≈ 1.2 × 10⁻¹⁰ m/s²
Status: Empirical constant. Fitted to data. The coincidence a₀ ≈ cH₀/(2π) is noted but unexplained.
MOND modifies Newton's second law below a₀. No explanation for why this specific value.
Synchronism
a₀ = cH₀/(2π) ← derived
Status: Derived from first principles. The acceleration scale emerges from the cosmic MRH and the coherence function.
The “coincidence” is explained: a₀ is the acceleration at which the coherence horizon reaches cosmic scales.
Head-to-Head Comparison
| Feature | MOND | Synchronism |
|---|---|---|
| a₀ origin | Empirical fit | Derived: cH₀/(2π) |
| Galaxy rotation curves | Excellent fit | Comparable fit (γ = 2) |
| RAR scatter | Predicts tight RAR | Predicts environment-dependent scatter |
| Wide binaries | Density-independent | Density-dependent (novel) |
| Galaxy clusters | Fails (needs DM) | Untested at this scale |
| Environment dependence | No | Yes (NP2, p = 5×10⁻⁶) |
| Extends to quantum | No | Yes (same γ, different N_corr) |
| Extends to chemistry | No | Yes (1,703 phenomena) |
| Free parameters | 1 (a₀) | 3 (A, B, β — derived + fitted) |
| Relativistic extension | TeVeS (problematic) | Built into coherence framework |
| CDM σ_int = 0.086 dex | Rejected at 32σ | Matches (z = +0.5) |
| Freeman's Law | Follows from a₀ | Derived from ρ_crit |
The Decisive Discriminator
Wide binary density dependence (TEST-02) is the cleanest discriminator. MOND predicts the anomaly is universal — same at all densities. Synchronism predicts it depends on local stellar density. Gaia DR3 data exists to test this. Zero cost, 6 months.
Honest Caveat
MOND has 40 years of empirical success and a large physics community behind it. Synchronism has been tested only internally over ~3 months. The comparison above is between a mature theory and an early-stage framework. Synchronism must earn its place through external validation, not internal comparisons.