Is Light a Particle, a Wave, or Something Else? A Space-Element Model with Density-Dependent Localization

Abstract: The nature of light has historically been described through the dual framework of wave and particle behavior. While classical electrodynamics successfully models light as a wave and quantum theory introduces the photon as a particle-like entity, the coexistence of these descriptions suggests an incomplete understanding of the underlying physical mechanism. In this work, we propose that light is neither fundamentally a particle nor a wave, but a propagating excitation of an underlying continuous medium, termed the Space Element (SE). The apparent particle-like behavior emerges from a density-dependent intrinsic localization mechanism, referred to as Primordial Centripetal Attraction (PCA). A minimal dynamical model is developed in which propagation is governed by a field equation, while localization arises from a gradient-dependent energy functional. This framework provides a unified interpretation of wave–particle duality without requiring dual ontology. We further outline experimentally testable predictions, including density-gradient–dependent light deviation and localization-width modulation.