Unified Electron-Photon Interaction Model through the USP Field Theory

*** This version reflects an early stage of the theory and is being refined to better match USP Field principles.*** This document presents a unified interpretation of electron and photon interactions with materials, using both established physics and the USP Field Theory—a foundational model based on stable spin-loop structures within a universal spin field. It explains why most interactions occur at the atomic surface layer, why structurally similar metals show dramatically different conductivity, and why photons pass through glass while electrons are blocked. Expanding upon classical explanations, the USP model treats electrons as energy loops stabilized by spin tension, offering intuitive insights into atomic resilience, charge behavior, and energy thresholds. The theory explains why atomic structures resist disruption unless field geometry is broken—highlighting that structure, not just charge polarity or energy levels, governs conductivity and transparency. The paper includes detailed analysis of: Surface-level particle-field interaction Atomic structure’s role in electrical conductivity Field-based explanation for photon transparency Why even high-energy electrons fail to pass through insulating materials Mechanical logic of atomic stability against electric charge disruption This unified view builds a bridge between experimental observations and deeper theoretical consistency, offering a new foundation for interpreting material behavior.