The Datum Line Stability Criterion (DLSC): An Equilibrium Admissibility Operator

The Datum Line Stability Criterion (DLSC) defines the conditions under which a reference datum representing system balance is admissible. A valid datum line exists only when boundary stability, resolution sufficiency, and conservation invariance are simultaneously satisfied. The construct distinguishes true equilibrium from apparent balance caused by boundary failure, insufficient resolution, or misinterpreted redistribution. DLSC functions as a non-interfering interpretive operator applicable across physical, logical, informational, and analytical domains. It does not modify underlying models or laws but constrains interpretation by verifying equilibrium admissibility prior to classification. The criterion is falsifiable in principle and applies wherever equilibrium claims depend on measurable stability conditions.