Perturbative Geometric Correction to the Nuclear Equation of State from M-Theory Compactification on G2-Holonomy Manifolds and Its Effect on the Neutron Star Maximum Mass

A perturbative correction to the nuclear equation of state has been derived from the backreaction of dense baryonic matter on the moduli fields of M-theory compactified on the Joyce orbifold T⁷/(Z₃ ⋉ I*) with G₂ holonomy and Betti numbers (b₂, b₃) = (27, 451). The compactification has introduced a density-dependent geometric potential Q_geo = C_LIG (n/n₀) E_F, where C_LIG = 0.05954 has been the matter-geometry coupling at the conical singularities, established independently through fifteen Standard Model observables in companion publications. The Akmal-Pandharipande-Ravenhall (APR4) equation of state has served as the baseline. The geometric correction has enhanced the maximum mass from M_max(APR4) = 2.214 M☉ to M_max(APR4+QGU) = 2.31 ± 0.07 M☉ (+4.3%), the canonical radius to R_1.4 = 11.08 km (+2.3%), and the tidal deformability to Λ_1.4 = 256 (+17%), all consistent with PSR J0740+6620, NICER, and GW170817 constraints. The coupling C_LIG = 0.05954 has been the same constant that has simultaneously constrained the Hubble tension, the S₈ tension, the primordial lithium problem, and the strong CP problem. Zero adjustable parameters have been introduced beyond those already present in APR4