Relational Composite Quantum Mechanics: An Information-Theoretic Interpretation Based on Local Observer Consistency

We propose a new interpretation of quantum mechanics, the core idea of which is that quantum superposition states are not mysterious physical entities, but rather the joint distribution of classical information obtained by local observers in a composite system. We assume that all systems are equivalent, and there is no fundamental distinction between "observer" and "observed". When multiple local observers independently observe the same system, if their observation results agree, the composite observer obtains a classical particle-like fact; if their observation results diverge, the composite observer obtains quantum wave-like behavior (a superposition state). We demonstrate that this "persuasion theory"—namely, that only when local observers reach an agreement can they persuade the composite observer—can naturally derive the formalism of quantum mechanics and perfectly explain the wave-particle duality in the double-slit interference experiment. This theory interprets quantum mechanics as a theory concerning the classical information mutually possessed by physical systems and their compositional relationships, and this description is complete.