Spin as a Dynamical Consequence of Spacetime Memory: A Time-Delay Field Interpretation Beyond the Dirac Framework

This work presents a focused theoretical extension of the Time-Delay Field (TDF) framework, previously introduced in “A Theory of Everything via the Five-Dimensional Delay Field Model” (Masarrat-Bakhsh, 2025). The present paper applies the TDF approach to the physical interpretation of spin, offering a complementary perspective to the standard Dirac formulation. Within the TDF framework, spacetime is endowed with intrinsic temporal memory, modeled through an effective time-delay field arising from a higher-dimensional (5D) structure. Spin is reinterpreted not as a purely algebraic or intrinsic quantum number, but as an emergent dynamical feature associated with delayed phase responses in non-Markovian field evolution. The characteristic spin-1/2 behavior and 4π rotational periodicity are shown to arise naturally from this delay-induced phase structure. The standard Dirac theory and its successful predictions are fully recovered in the limit of vanishing delay, ensuring consistency with established relativistic quantum mechanics. This work does not propose a replacement of the Dirac framework, but rather provides a causal reinterpretation that may offer deeper insight into the origin of spin and spin–orbit coupling. The paper is intended as a conceptual and foundational contribution, suitable for discussions in theoretical physics, quantum foundations, and spacetime-based interpretations of quantum phenomena.