Trieste Quantum Seminar Series:

A Microscopic Branch-Exchange Mechanism for Diósi-Penrose- Like Decoherence

Prof. Moslem Zarei
Department of Physics, Isfahan University of Technology, Iran

Abstract: The Diósi–Penrose (DP) framework provides an effective phenomenological model of gravitationally induced decoherence (GID), but its underlying microscopic dynamical origin remains unclear. In this talk, I will present a microscopic framework for GID based on the quantum Boltzmann equation (QBE).
I will show how a massive quantum particle can be represented as an effective two-level branch system, with the two branches interacting through graviton exchange. In this framework, gravitational decoherence emerges dynamically from the forward-scattering sector of the QBE, rather than being introduced as a phenomenological decoherence rate.
I will demonstrate that, in the non-relativistic regime, the resulting decoherence rate reproduces the characteristic scaling of the Gaussian-regularized DP model, while naturally incorporating finite-history effects that are absent in the conventional static DP self-energy. I will also discuss how these memory effects modify the dependence of the decoherence rate on the spatial separation and mass of the superposed branches.