Quantum diffusion in gravitational waves backgrounds
Serge Reynaud
Laboratoire Kastler Brossel
Wed, May. 12th 2010, 14:15
Salle Claude Itzykson, Bât. 774, Orme des Merisiers
The value of the Planck mass (22$\mu$g) may lead to the idea that intrinsic fluctuations of spacetime are responsible in some manner for the existence of a natural borderline between quantum and classical worlds. We propose quantitative answers to this question by considering the diffusion and decoherence mechanisms induced on quantum systems by the stochastic gravitational waves (GW) backgrounds generated at the galactic and cosmic scales. This universal fluctuating environment indeed blurs quantum interferences on macroscopic systems (large masses), while leaving essentially untouched those on microscopic systems (small masses). We give relevant numbers in the context of ongoing progress towards more and more sensitive matter-wave interferometry. Similar ideas are also worthy of attention in the context of quantum information. For example EPR correlations encoded on photon polarizations are affected by the exposition to the GW backgrounds, and one can wonder whether or not, and to what extent, the correlations survive propagation on long distances.
Contact : ccaprini