Structural Spatial Algebra: Space Begins at $\mathcal{F}(\psi_i, \psi_j) \ne 0$

This work develops a self-contained framework of Structural Spatial Algebra, where space is no longer a geometric background but a directed coupling graph of modal dependencies. The foundational Theorem 3 states that space arises from modal interactions whenever structural residuals δ(ψj ) depend on prior modal states ψi, encoded in the coupling tensor F(ψi,ψj ). We show that structural space S= (Ψ,⇝) is not defined by coordinates, but by causally meaningful directional relations among collapse events. This formulation is empirically validated on real gravitational wave data (GW170817), reconstructing an observable space of modal tension. The results demonstrate that time is a wave over space, and that space itself is born where coupling begins.