Title: Cross‑Torsion Pressure as a Candidate Mechanism for Vacuum Modulation Abstract: This document records a conceptual discovery: the crossing of torsional fields may create a measurable pressure term capable of influencing vacuum energy density. The idea arose from private experimentation and is presented here as a reproducible hypothesis. Background: Current physics treats torsion in the Einstein–Cartan extension of relativity, but the observable magnitude is predicted to be extremely small. The hypothesis presented here suggests that intersecting torsion domains could amplify local spin‑density coupling. Hypothesis: Cross‑torsion pressure between non‑parallel spin domains modifies local curvature, producing an effective stress–energy contribution that could appear as additional mass density or negative pressure. Predictions and Possible Tests: 1. Minute deviations in Casimir‑type vacuum pressure when two rotating magnetic or acoustic lattices intersect. 2. Small gravitational anomalies in high‑spin plasmas. 3. Phase‑dependent modulation of vacuum birefringence in precision optical cavities. Next Steps: Define experimental geometry, required sensitivity, and theoretical bounds from existing data.