Gravitation as an Evanescent Vacuum Mode: From Propagation at c to Asymptotic Elasticity in the TUO–NS Framework.

We present a non-relativistic conceptual clarification of gravitation within the TUO–NS framework, where both electromagnetic propagation and gravitational interaction emerge from a single reconstructed vacuum dynamics. In this approach, the speed of light $c$ characterizes the intrinsic stiffness and causal propagation limit of the vacuum, independently of matter. Localized particles are identified with unique stationary saturation modes of this medium. We show that the asymptotic Yukawa tail of such a mode is not an ad hoc assumption but the stationary imprint of the same linear operator that governs free propagation at speed $c$. Long-range gravitational attraction is derived from the energetic overlap of these asymptotic tails in the linear regime of the vacuum. In the near-critical saturation limit, this interaction naturally reduces to a Newtonian $1/r$ potential, with the gravitational constant $G$ emerging as a derived quantity controlled by vacuum elasticity rather than introduced as a fundamental parameter. Gravitation is thus interpreted as a confined, evanescent remnant of vacuum propagation, while gravitational waves arise as rebalancing disturbances propagating in the unsaturated vacuum at speed $c$. The present work deliberately restricts itself to the Newtonian and conceptual level and does not aim to reproduce the full relativistic tensorial structure of General Relativity. It provides a coherent microscopic foundation for long-range interaction compatible with causal propagation in a unified vacuum framework.