Compton Scattering in the Rotating Spinor Wave Model: Huygens-Principle Analysis and Comparison

Compton scattering is analysed in the Rotating Spinor Wave (RSW) model, where both the electron and photon are treated as finite-size Spacetime Action Packets (SAPs). The scattering amplitude is obtained as a coherent Huygens superposition over all spacetime points in the electron–photon overlap region, without renormalisation or Feynman diagrams.

We show that:

•  the Compton frequency shift ω′(θ) emerges exactly at all angles from interference within the electron SAP;

•  the Thomson polarisation factor (1 + cos²θ)/2 appears naturally from the transverse photon field;

•  the electron SAP yields a charge form factor F(q) = exp(−q²σ_e²/4) (σ_e = 1.597 λ_C);

•  the angular shape of the differential cross-section agrees with the Klein–Nishina formula to within 0.07 % (std) in the Thomson limit (ω_γ = 0.001 m_e c²) and 4.2 % at ω_γ = 0.1 m_e c², with deviations scaling as ω_γ^{0.91} and vanishing as ω_γ → 0.

The physical origin of the integration is Axiom 2 of SWQ theory: since the spacetime point of interaction is not identified, all points in the overlap volume must be summed as complex amplitudes. At high photon energies ω_γ ≫ ħc/σ_e ≈ 320 keV the coherence condition breaks down, naturally explaining why high-energy experiments detect no electron substructure.

The absolute normalisation (r_e² prefactor) remains an open task requiring identification of the RSW ring-current matrix element with the coupling constant. This work demonstrates that the RSW/SWQ framework reproduces the essential features of Compton scattering from first principles using only wave-packet overlap and Huygens’ principle.