Relativity as Geometry, Coherence as Transport

We develop a coherence-first reformulation of relativistic kinematics and transport dynamics within the Universal Field Tensor (UFT) framework. In this formulation, relativistic structure emerges from invariance of a fundamental coherence action rather than from an a priori geometric postulate about spacetime. Local Lorentz symmetry appears as the tangent symmetry group of a UFT-induced coherence metric, while departures from standard special relativity arise as controlled first-order corrections governed by a coherence deformation tensor. The central technical result is a unified observable functional that controls clock-rate shifts, Doppler deviations, and inertial mass-energy response through the same trajectory contraction. This creates a multi-channel experimental strategy: clock, Doppler, and inertial measurements can jointly bound or reveal the same deformation structure. The paper further distinguishes null coherence carriers, which preserve the invariant propagation boundary at leading order, from reduced persistent systems whose measured rates and inertial responses may acquire first-order coherence-modulated deviations. Additional theorem boxes develop acceleration-memory signatures, recovery limits, perturbative consistency, coherence compensation, transport action, Noether current, stress-energy, and exchange closure. The result is a contained Relativity 2.0 framework: standard special relativity is recovered in the appropriate limit, while a falsifiable first-order extension is formulated through coherence action, UFT tangent symmetry, and controlled deformation dynamics. Keywords Relativity 2.0; Universal Field Tensor; coherence action; tangent Lorentz symmetry; coherence metric; first-order deviations; clock-rate shifts; Doppler residuals; inertial response; acceleration memory; coherence transport.