Title: "How to detect the quantum mechanical behaviour of a macroscopic object?"

After Zeilinger's successful $C_{60}$ interference experiment, since molecules larger than $C_{60}$ don't want to fly, a different idea was needed to proceed towards heavier objects. The new proposal was to use mirrors on nanomechanical oscillators, coupled to a cavity. The photon interacts with the mirror, and from the state change of the photon, indirectly we can learn something about the motion of the mirror. Decoherence models have been applied to this proposal to locate a region of parameters (like temperature, quality factor of the resonator, frequencies of the mirror and the laser) where signals from the photon detectors can be used to identify quantum mechanical behaviour of the mirror.