The reported annual oscillation in nuclear decay rates (), correlated with the Earth-Sun distance, remains one of the most persistent unverified anomalies in modern physics. Attributed variously to instrumental systematics or solar neutrino interactions, the effect lacks a unified theoretical mechanism, primarily due to inconsistent signal amplitudes across different laboratories. In this work, we demonstrate that these fluctuations are the kinetic signature of the Vacuum Coupling Invariant (), a fundamental dimensionless constant previously derived from the proton radius discrepancy. We propose that the solar gravitational gradient induces a directional stress on the local vacuum metric, which modulates the quantum tunneling probability. By treating this interaction as a vector projection onto the local laboratory vertical, we derive a latitude-dependent correction law: . This geometric model resolves the historical discrepancy between data from Brookhaven National Laboratory (N) and the Physikalisch-Technische Bundesanstalt (N). The model accurately predicts the robust signal observed at Brookhaven ( predicted) and explains the attenuated signal reported in Germany ( predicted). These results suggest that the "Jenkins-Fischbach effect" is a reproducible, latitude-dependent detection of vacuum metric elasticity, offering a new window into the coupling between gravity and quantum mechanics.
Luis Rodrigues (Sat,) studied this question.