  The gap between the predictions of collapse models and those of standard
quantum mechanics widens with the complexity of the involved systems.
Addressing the way such gap scales with the mass or size of the system being
investigated paves the way to testing the validity of the collapse theory and
identify the values of the parameters that characterize it. Here, we review the
recently proposed non-interferometric approach to the testing of collapse
models, focusing on the opto-mechanical platform.
