MOND from 5D Geometry: Quadrature Addition and SPARC Validation

We derive the MOND interpolating function from 5D geometry. Gravitational acceleration has two perpendicular components: the standard 3D Newtonian component and a W-direction component arising from a Hubble-scale fifth dimension. These add in quadrature, yielding nu(x) = sqrt(1 + 1/x). We test this formula against 175 galaxies from the SPARC database, finding lower chi-squared than both "simple" and "standard" MOND interpolating functions. The theory explains solar system screening through a binary coherence criterion and connects the MOND acceleration scale to cosmology via a_0 = cH_0/(2pi).