The Spiral Structure Model: A Geometric Phenomenology of Wave-Particle Duality, Spin, and Electromagnetic Coupling

The Spiral Structure Model (SSM) is a phenomenological model in the tradition of Bohr's early atom: confined to kinematics and geometry, it trades dynamical depth for ontological clarity and experimental exposure. Three postulates suffice. (I) The photon is a pointlike energy quantum in uniform helical motion, with axial and circulation speeds both equal to c; (II) physical space is an elastic, relativistically covariant medium that sustains vortex excitations; (III) the electron is a stable topological vortex defect of that medium. From these postulates, with every step carrying an explicit epistemic label, the model obtains the photon's circulation angular momentum mcrγ = ħ as a consistency theorem and identifies it with the photon spin; logarithmic vortex confinement with no free parameters; the two polarization states and the absence of a longitudinal mode; orbital angular momentum as an ensemble property; the electron's 720-degree periodicity and spin ħ/2 from π₁(SO(3)) = ℤ₂. The same postulates yield the fine-structure constant as a ratio of structural scales and the free radiation field as a retarded ensemble moment satisfying the wave equation exactly. They also yield a phase-coupling account of two-slit interference and a double-helix ontology of entangled pairs that reproduces the CHSH value 2√2. Three falsifiable discriminants are stated with explicit falsification criteria: a wavelength-locked on-axis void in the photon's detection profile, a spin-dependent electron form-factor window near Q = mc, and a circulation-periodic component in entangled-pair coincidence timing.