Primordial Gravitational Waves from E8-X Inflation

We derive the primordial gravitational wave spectrum predicted by the E8-X Unified Field Theory. The inflaton is identified with the same field component responsible for family symmetry breaking and axion dynamics, with a potential uniquely determined by the E8 scalar potential: V(φ) = V₀(1 - φ²/M_GUT²). From slow-roll inflation we obtain the tensor-to-scalar ratio r ≈ 0.01–0.03 and the gravitational wave spectral index n_T ≈ -0.002 to -0.006. These values lie within current CMB limits and fall precisely within the optimal sensitivity window of the upcoming CMB-S4 experiment. This provides a sharp, falsifiable cosmological signature of the E8-X theory.