This paper presents a kinematic challenge to the standard assumption of a perfectly elastic vacuum. By performing an astrometric audit of 955 extragalactic sources in the Boötes North sector (RA 205. 25) using Gaia DR3 data, I identify a non-Newtonian Plug Flow velocity profile. A core Anisotropy Ratio of 2. 47, indicating a coherent "Metric River" rather than random gravitational motion. Observation of a suppressed core jitter (= 6. 55 mas/yr) relative to a shearing periphery (= 8. 45 mas/yr), a classic signature of Bingham Plastic flow. I propose that the Hubble Tension is a result of local metric slip (Vₒ₋₈) within high-stress vacuum conduits, triggered by a vacuum yield threshold of 39 MeV. Unlike dark energy models which rely on unseen scalars, this model provides an auditable, mechanical explanation for the 2, 792 km/s velocity overshoot and the late-universe expansion discrepancy.
Buquoi Max (Mon,) studied this question.