Minimal Assumptions for Phase-Referenced Interference Tests of Structured Phase-Dependent Deviations

This note identifies the minimal conditions required for a phase-referenced interferometric test of structured phase-dependent deviations. The test relies on the quadrature representation: \ I () = C + V[A + B, \] which enables a deviation metric: \ ₙ = (Aₙ - A₀) ² + (Bₙ - B₀) ². \ Three assumptions are required: quadrature decomposability of the interference signal; availability of a stable phase reference; and controlled phase-structure input. Without phase referencing, all deviations collapse into a phase offset: \ A + B = V (-), \ making the test non-diagnostic. Under these conditions, the protocol reduces to a falsifiable signature: \ ₀ 0, ₙ, phase-locked quadrature structure. \ The result is model-independent: the validity of the test depends only on measurement structure, not on any specific underlying theory.