Charge, Inertia, Stepped Variable Mass Increase Yielding a Variable G: Extensions of the Field-Based Machian Framework

Abstract Earth's Length of Day, measured continuously by atomic clocks since 1962, oscillates with a period of approximately 5.9 years. Jupiter's half-orbital period is 5.93 years. Jupiter's direct tidal effect on Earth's rotation is ten orders of magnitude too small to account for the observed variation. No mainstream mechanism explains this period match. Independent laboratory measurements of Newton's gravitational constant G, conducted by multiple teams worldwide using fundamentally different experimental methods, show an oscillation at the same period and phase — correlation significance 0.99764. The Machian inertial field framework provides the physical connection: Jupiter's orbital position modulates the local Machian field density, producing simultaneous real variation in both Earth's rotational inertia and the effective gravitational parameter G. The Length of Day correlation is established observational fact. G is not a universal constant. These conclusions rest on mainstream data alone. Building on this observational foundation and the companion paper's field-based Machian mechanism DOI: 10.5281/zenodo.19519227, this paper develops three extensions. First, electric charge is identified as the primary coupling mechanism through which fundamental fermions acquire mass from the Machian inertial field — a claim supported by the fermion mass spectrum spanning twelve orders of magnitude. Second, the neutrino, as the only fundamental fermion carrying zero electric charge, provides direct observational support: its near-zero mass, near-c velocity, and near-complete transparency to ordinary matter all follow from a single property — zero charge, zero Machian coupling. Third, newly created or field-stripped matter gains mass in discrete steps driven by QCD vacuum condensate phase transitions as the Machian field builds — connecting to Arp's quasar evolutionary sequence, Tifft's reported redshift quantization, and multiple absorption components observed in BAL quasar spectra. The framework is compatible with the Standard Model while addressing foundational questions it leaves open. Ten specific testable predictions are identified, several requiring only reanalysis of data already in hand.