Einstein's Betrayal: How the 1915 Einstein-de Haas Experiment Proved the Existence of a Rotating Vacuum and Was Subsequently Abandoned

In January 1915, Einstein and de Haas experimentally demonstrated that magnetization induces mechanical rotation, proving electromagnetic fields possess real angular momentum. Ten months later, Einstein published General Relativity denying any physical vacuum substrate. This paper documents this historical contradiction through primary sources, reviews 109 years of experimental confirmations (1915-2024), and demonstrates that Structured Vacuum Theory resolves the paradox by recognizing magnetic fields as vorticity in a 23-channel helical vacuum structure. Includes analysis of modern technological evidence (MRI torques, tokamak gyroscopic effects) and the Lorentz-Einstein debate on ether reality.