Macroscopic quantum resonators in space

We propose a space-based experiment that aims at testing the predictions of quantum theory against those of macrorealistic models. The proposed experimental layout, including a thermal shield to thermally isolate the setup from the spacecraft. Using this setup, a dielectric nanosphere is optically trapped and then cooled to the ground state. Then the particle is released, and its wavefunction will expand. After a certain time, a UV pulse is sent through the center of the wavefunction. If the UV light is not scattered, the wavefunction will be divided in two regions that will interfere. In order to parametrize the decoherence predicted by quantum theory or by other theoretical models, we introduce the Coherent-Expansion Distance; that is the distance between the two parts of the wavefunction that we can achieve and still see good interference afterwards. We will describe the proposed experimental layout, the technical prerequisites, and we will describe the conditions under which the proposed experiment should be able to distinguish between quantum theory and several distinct macrorealistic models like the K-Model, the Penrose Model, and the GRW Model.