Extended Falsifiability of Quantum-Geometry Dynamics: Structural Predictions Beyond the Constant-Grounding Programme

This paper is the companion to P14 (Grounding Quantum-Geometry Dynamics, https://doi.org/10.5281/zenodo.20369889) in the QGD/MPDT programme. P14 establishes four experimental Pathways by which QGD's four free constants — the gravitational coupling k, the preonic distance x, the fundamental momentum c̃, and the preonic mass unit m̃ — can be empirically constrained. The present paper identifies a second tier of falsifiability targets: structural predictions that are either testable qualitatively now, without knowing the constants, or become quantitatively testable once the Pathway 1–3 constants are in hand. The tests probe QGD structural commitments that the four Pathways do not reach: the electromagnetic-preonic mechanism of magnetic field generation, the free-preon(+) background as the physical medium of that generation and as the counterpart of dark matter, the corpuscular photon ontology, the forbidden momentum spectrum governing superconductivity, the distance-independence of p-gravity at short range, and the absolute preonic frame. The central and most immediately testable prediction is the Zeeman-galactocentric test: because the magnetic moment of a polarising particle is proportional to both its spin angular momentum and the local free-preon(+) density (P11, Ch. 10), and because free-preon density decreases with galactocentric radius (P13), Zeeman-measured magnetic field strengths of population-matched stellar and interstellar medium samples should be systematically stronger near the galactic centre than at the galactic outskirts. This prediction is stated in ratio-testable form — μ(r₁)/μ(r₂) = dens(p⁺)(r₁)/dens(p⁺)(r₂) — in which the unknown proportionality constant cancels, making the test executable now using the Milky Way rotation curve as an empirical proxy for the free-preon density profile. Three independent observational tiers are specified: ISM Zeeman splitting (21 cm HI and OH/CN masers), population-matched stellar Zeeman broadening, and pulsar spin-down field estimates. The coherent prediction of the same fractional enhancement across all three structurally unrelated tiers is the differential signature that distinguishes QGD from standard astrophysical dynamo models. Eight further tests are catalogued in a tiered dependency structure: Bell correlation distance-dependence and temporal variance (Tier 0); the p-gravity floor at short range (Tier 0/1); Cooper-pair suppression with maintained forbidden momentum condition (Tier 0/1); isotope effect direction in superconductors (Tier 1); photon momentum conservation in transit and absorption threshold shift in extreme gravity (Tier 2); cosmic void interior gravitational profile (Tier 2); and one-way light speed seasonal modulation (Tier 3). A 13-row unified falsifiability table consolidates all tests with dataset, QGD commitment, and falsification condition for each. This paper is part of the QGD/MPDT paper series. The foundational monograph is P11 (https://doi.org/10.5281/zenodo.19584666). Continuous functions used in the paper are finite prescriptions in the sense of P36 (https://doi.org/10.5281/zenodo.20652019).