Mass Field Buoyancy Theory (MFBT): A Mechanistic Reinterpretation of Gravitational Acceleration as Buoyancy in a Field-Structured Medium

The mechanism underlying gravitational acceleration has remained unresolved in classical and relativistic physics. Newton's law describes the magnitude of gravitational attraction without explaining its physical cause. General relativity geometrizes gravity as spacetime curvature without identifying the medium through which curvature propagates or why mass produces it. We propose Mass Field Buoyancy Theory (MFBT), a mechanistic reinterpretation of gravitational acceleration as buoyancy-like displacement of mass within Earth's field-structured medium. MFBT identifies five physically recognized mediums — air, water, plasma, electromagnetic field medium, and structured spacetime — all of which exhibit density gradients, layering, and buoyancy-like behavior. We treat the near-Earth environment as a composite field medium whose effective density is derived from measurable electromagnetic and gravitational potential field quantities. The resulting acceleration equation reproduces standard near-surface gravitational acceleration at leading order while predicting measurable deviations in regions of anomalous electromagnetic field density or gradient. a_MFBT(r) = (1 - rho_m(r)/rho_o) * g_f(r) Additionally, the same medium potential that governs mass settling provides a natural account of gravitational time dilation, directly connecting MFBT to recent quantum clock experiments. A dynamic extension derives a wave equation for medium density perturbations, predicting wave propagation at c consistent with LIGO observations and a second EM-driven wave mode at c/sqrt(3) unique to MFBT. MFBT is calibrated to Earth in this paper. The framework extends structurally to other bodies by substituting planetary field values.