A 5D Spacetime-Matter Framework with Spacelike Extra Dimension: Induced Matter, Holographic Entanglement, and THz Resonances (Master-Framework V8.0)

English Abstract: We formulate a comprehensive five-dimensional spacetime-matter (STM) framework that embeds four-dimensional general relativity into a dynamical 5D bulk. To preserve causal integrity and ensure quantum field-theoretic unitarity, the extra dimension is defined strictly as a spacelike coordinate with metric signature (-, +, +, +, +) and G_44 = +Phi^2. Invoking the 5D vacuum field equations (5)R_AB = 0 (Wesson's induced matter formalism), matter and field tensions in our 4D hypersurface emerge as geometric projections of the bulk energy-flux tensor F^nu. Quantum entanglement is re-formulated holographically via spacelike bulk geodesics (ER=EPR), avoiding closed timelike curves. Furthermore, galactic rotation curves are derived ab-initio via linear perturbations of the effective Wesson potential, yielding a flat asymptotic velocity profile at approx. 220 km/s without dark matter, protected by a nonlinear Vainshtein-type screening mechanism on solar system scales. Empirical falsifiability is established through predicted THz-induced proton resonance anomalies in low-density amorphous (LDA) ice at millikelvin temperatures.