Phase-Coherence Correction to the Indian Ocean Geoid Low: A Zero-Parameter Cross-Domain Prediction from the Geometric Universe Framework

The Indian Ocean Geoid Low (IOGL) is the most negative geoid anomaly on Earth when defined relative to the reference ellipsoid (Chambat et al. 2010). Existing mantle-convection models reproduce the IOGL's location and overall pattern, with reported regional correlations that depend on tomography and viscosity choices (of order 0.7–0.9 in representative cases; Ghosh et al. 2017; Pal & Ghosh 2023). Regional variance reductions of 62–77% have been achieved, leaving a quantifiable residual. We propose a correction arising from the Geometric Universe Framework's phase-coherence mechanism, originally introduced in the context of fundamental constants derived from S³ geometry. The correction is constructed with no free parameters adjusted to geophysical data: the framework parameter σ² = π²√5/2 ≈ 11.035 is fixed to the same value used in prior constants work (yielding α⁻¹ = 137.035999…; Graham 2026, Zenodo), while all geophysics-side inputs — refractive index contrast (Δn = 0.08), melt fraction (~2%), plume temperature excess (+300 K), and compensation factors — are taken from independent laboratory measurements, standard petrology, and the published IOGL literature. The extension of σ² from its particle-physics role to a gravitational coupling width is a hypothesis of the present paper. The key physical insight is that gravitational coupling modifications from partial melting are uncompensated by dynamic topography, unlike density anomalies which are ~86% compensated at mid-mantle depths. Under these inputs, the model yields a predicted gravity anomaly of −50.9 mgal versus the observed −50 mgal. The reader need not accept the parent framework to evaluate this prediction — the critical requirement is only that σ² was determined before any geophysical data was consulted. A natural control experiment is provided by the Hudson Bay geoid low (cold downwelling, no partial melt), where no coherence correction is expected and where standard density-based models account for the full observed signal. Six falsifiable predictions are presented, including a direct computational test implementable in existing mantle convection codes such as CitcomS. If independently reproduced, this would provide an unusually stringent cross-domain test of the framework.