New insights on the quantum-classical division in light of Collapse Models

Abstract: We argue, in light of Collapse Model interpretation of quantum theory, that the fundamental division between the quantum and classical behaviors is analogous to the division of thermodynamic phases. A specific relationship between the collapse parameter $(\lambda)$ and the collapse length scale ($r_C$) plays the role of the coexistence curve in usual thermodynamic phase diagrams. We further claim that our functional relationship between $\lambda$ and $r_C$ is strongly supported by the existing IGEX collaboration data. This result is preceded by a self-contained discussion of quantum measurement theory and the Ghirardi-Rimini-Weber (GRW) model applied to the free wavepacket dynamics.