Casimir–Gravitational Equilibrium Condition (CGEC): A Geometry-Driven Regime Criterion for Vacuum-Induced Decoherence Tests

This short note refines a previous proposal: that a physical configuration in which Casimir vacuumenergy matches Penrose–Diósi gravitational self-energy (EG ) may produce a transition relevant toobjective-collapse models. We provide a cautious and experimentally grounded formulation,introduce the Casimir–Gravitational Equilibrium Condition (CGEC), expand scaling analysis,discuss decoherence constraints, and identify measurable photon-based signatures. This model introduces the Casimir–Gravitational Equilibrium Condition (CGEC), outlining a measurable regime where vacuum fluctuations balance gravitational self-energy, potentially linking quantum vacuum structure to gravitational thresholds