Gravity as Residual Electrodynamics A Machian Synthesis of Atomic Geometry and Vacuum Structure

This paper presents a synthesis of independently developed results spanning seventy years of heterodox and mainstream literature, arguing that gravitation, inertia, and the geometric formalism of General Relativity are macroscopic expressions of a single underlying electromagnetic vacuum structure. We trace a coherent chain: (1) gravitational N-body dynamics are conventionally calculated with electromagnetic fields excluded despite their non-zero presence at every scale, an omission that is defensible only if EM contributions are negligible — an assumption chaotic systems do not generally permit; (2) Spears (2010) demonstrated that the Newtonian gravitational constant G can be derived from purely electrostatic atomic parameters to within 0.2% of the CODATA value, via a mechanism in which the geometric mismatch between a point-like nucleus and a distributed electron cloud produces a residual dipole interaction that is rectified to attraction in the presence of neighboring atoms and sums via the Hamaker integral to an effective 1/r² macroscopic force; (3) this mechanism is inherently quantum mechanical, as it depends on irreducible zero-point fluctuations of atomic charge distributions, offering a route to the unification of gravitation with quantum theory that does not require a graviton or a separately quantized gravitational field; (4) the same zero-point electromagnetic field has independently been proposed by Haisch, Rueda, and Puthoff (1994) as the origin of inertia, and by Sciama (1953) and Wheeler and Feynman (1945) as the transmission mechanism for Mach's principle, such that F = ma and E = mc² can both be read as expressions of a cosmological electromagnetic vacuum field rather than as primitive mechanical relations; (5) Dicke (1957), Wilson, and Puthoff subsequently showed that representing the vacuum permittivity ε₀ and permeability μ₀ as spatially varying near a mass — a Polarizable Vacuum — reproduces the three classical tests of General Relativity, including Mercury's perihelion precession and gravitational light deflection, without requiring spacetime itself to be physically curved; and (6) this framework predicts two independent axes of variation in the gravitational constant — a temporal axis, consistent with the previously reported 5.9-year correlation between G measurements, Earth's length-of-day, and Jupiter's orbital period (Anderson et al. 2015), and a structural axis, in which G should depend measurably on the electron orbital geometry of the test masses used in precision torsion-balance experiments. We argue this framework does not reduce General Relativity but grounds it, in the same sense that statistical mechanics grounds thermodynamics, while resolving the hierarchy problem, the gravity-quantum mechanics incompatibility, and the persistent unexplained scatter in precision G measurements. The framework is presented explicitly as a Popperian conjecture with identified falsification criteria, and a companion paper develops a concrete experimental test of the structural G-variation prediction.