Operator Status of the Wavefunction: Admissibility, Observables, and Regime-Defined Physical Content (IM-E003, v0.3)

This document is part of the Informational Mechanics (IM) framework and is published in the IM-E (Measurement & Operators) series within the IM v0.3 corpus. The paper analyzes the physical status of the quantum-mechanical wavefunction under admissibility constraints. Rather than adopting an ontological position (ψ-realism or ψ-epistemicism), the analysis evaluates when the wavefunction carries operator-defined physical content within a declared quantum-mechanical regime. Within Informational Mechanics, physical content is defined only where operator-implementable observables, stable invariants, and regime-bounded comparability are available. The wavefunction is therefore treated as a regime-defined representational object whose physical meaning depends on the continued admissibility of the operators required to define and compare its associated observables. The paper introduces no new axioms, collapse models, hidden variables, or empirical fits. Its contribution is structural and operational: to clarify when statements about the wavefunction are scientifically meaningful and when they extend beyond operator-defined structure.