Spontaneous Wave-Function Collapse: a Solution to the Measurement Problem and a Source of the Decay in Mesonic Systems

Spontaneous Wave-Function Collapse: a Solution to the Measurement Problem and a Source of the Decay in Mesonic Systems Dynamical reduction models propose a solution to the measurement problem in quantum mechanics: the collapse of the wave function becomes a physical process. We consider the two most promising collapse models, the QMUPL (Quantum Mechanics with Universal Position Localization) model and the mass-proportional CSL (Continuous Spontaneous Localization) model, and derive their effect onto flavour oscillations of neutral mesons. We find that the dynamics of neutral mesons depends on the very assumptions of the noise field underlying any collapse model, thus the physics of the noise field becomes investigatable for these particular systems. Secondly, we find that the decay property of the mass eigenstates can be dynamically generated by the spontaneous collapse in space. Taking collapse models seriously we conclude that accelerator facilities have measured the absolute masses of eigenstates of the Hamiltonian giving raise to decay; this in turn is at the same footings as the mass difference giving raise to the flavour oscillations (predicted also by standard quantum mechanics). Thus dynamical reduction models can cover the full dynamics, oscillation and decay, of neutral mesons.