Testing Quantum Coherence Reconstructibility in Mesoscopic Systems

This work introduces an operational framework to test whether quantum coherence remains fully reconstructible in mesoscopic systems under controlled experimental conditions. The approach combines statistical state reconstruction with controlled variation of a parameter λ under calibrated environmental decoherence. Deviations from standard predictions are quantified by a covariance-based observable comparing reconstructed and predicted states. A minimal phenomenological parametrization is introduced in terms of an effective parameter Ξ, combining mass, spatial delocalization, interrogation time, and gravitational configuration. Two generic behaviors are considered: continuous residual contributions leading to an irreducible floor, and threshold-like effects associated with regime transitions. The framework defines a direct falsification criterion: the absence of parameter-dependent deviations constrains residual contributions, while a reproducible dependence signals a breakdown of reconstructibility, interpreted as a limitation of accessible information rather than a modification of quantum dynamics. Analysis of current levitated optomechanical experiments shows that achievable sensitivities constrain residual contributions for covariance-based observables. These bounds are indirect, as existing experiments are not optimized for the proposed protocol, motivating dedicated implementations.