The Quantum Consensus Principle A Thermodynamic Theory of Quantum Measurement

We introduce the Quantum Consensus Principle (QCP), a first-principles framework that provides a purely dynamical derivation of the quantum measurement process without modifying the Schrödinger equation. By treating the apparatus–environment complex as an open quantum system, we show that measurement outcomes emerge from a thermodynamic selection process governed by large-deviation dynamics. Central to the theory is the derivation of a universal selection potential, Φᵢ, which is uniquely determined by the BKM information geometry of the thermal environment and linked to microscopic Hamiltonian parameters via Green–Kubo relations. We rigorously demonstrate that the conditioned system state follows a Hellinger-contractive supermartingale, converging almost surely to unique pointer states. Unlike standard postulates, QCP derives the Born rule as a specific neutrality limit and predicts measurable, apparatus-dependent deviations for non-ideal observers. Furthermore, the theory establishes a characteristic non-monotonic scaling of collapse timescales, providing a clear path for experimental falsification. This work bridges the gap between quantum information theory and non-equilibrium thermodynamics, identifying measurement as a fundamental consensus phenomenon in macroscopic systems.