Prior Hypothesis Note: 1963 Pivot in Cross-Domain Stabilization

This upload documents a preliminary hypothesis proposing 1963 CE as a pivot epoch for stabilization observed in desparate measurement domains, including superconducting qubit coherence times and baryon acoustic oscillation (BAO) estimates. The note is exploratory and phenomenological in nature. No causal mechanism is asserted. The purpose of this record is to establish a timestamped public hypothesis prior to subsequent modeling and testing.