The Duality of Mass: A Unified Principle from Orbital Mechanics to Cosmic Structure

This paper presents the Mass Duality Principle,a new theoretical framework proposing that the mass of a body in a bound system is not a single invariant but exhibits dual aspects: a Kinematic Mass governing momentum and a Coupling Mass governing interactions with force fields. This principle is grounded in a fundamental relation derived from the conservation of angular momentum with relativistic mass variation. We demonstrate that this principle offers a unified interpretation for two major puzzles in physics. In astrophysics, it reinterprets galactic rotation curves, explaining the anomaly attributed to dark matter as a manifestation of mass duality without requiring non-baryonic matter. In quantum physics, it provides a novel perspective on atomic binding energy. This work challenges a foundational assumption and proposes a cohesive narrative bridging celestial and quantum mechanics, suggesting that context-dependent mass is a fundamental property of bound systems.