The Neutron as a Composite Soliton of the Rotor Field Equation

The Rotor Dynamics Framework models the vacuum as a four-dimensional rotor manifold supporting circulating curvature structures described by the Rotor Curvature Field. Previous papers in this series established the Rotor Field Equation and demonstrated that elementary particles may arise as localized soliton solutions of this nonlinear curvature field. In the present work the neutron is interpreted as a composite soliton consisting of a proton rotor core coupled to an electron-like curvature sheath. The combined configuration forms a stationary solution of the Rotor Field Equation in which two interacting curvature domains produce a localized core–sheath rotor structure embedded in the vacuum manifold. Stability of the composite configuration arises from energetic minimization, topological circulation constraints, and nonlinear curvature feedback between the core and sheath rotors. Unlike the proton and electron solitons, the neutron configuration is metastable when isolated due to a torsional phase degree of freedom between the rotor layers that stores approximately 1.3 MeV of curvature energy. Relaxation of this torsional coupling produces the separation of the sheath from the core, corresponding to β⁻ decay of the free neutron. Environmental interactions within nuclei increase the effective coupling stiffness, stabilizing neutrons embedded in nuclear systems. These results provide a field-theoretic realization of the geometric neutron rotor model and complete the description of the neutron as a composite soliton of the Rotor Field Equation.