Abstract Models of gravitational decoherence are not commonly applied to ultra-relativistic systems, including photons. As a result, few quantum optical tests have been developed. In this paper, we generalize the model Anastopoulos and Hu (2013 Class. Quantum Grav. 30 165007) model, originates from bath stochastic perturbations, possibly fundamental origin. We derive master equation for general...

background: high density concrete is extensively used for efficient radiation attenuation in radiotherapy rooms and nuclear reactors. over the past eight years, some efficient galena-based concrete samples for shielding x or gamma rays was produced. the goal of this study was to produce a novel high density concrete against neutron and photon radiations using tourmaline and galena. materials an...