  A novel interpretation of the quantum mechanical superposition is put
forward. Quantum systems scan all possible available states and switch randomly
and very rapidly among them. The longer they remain in a given state, the
larger the probability of the system to be found in that state during a
measurement. A crucial property that we postulate is quantum inertia, that
increases whenever a constituent is added, or the system is perturbed with all
kinds of interactions. Once the quantum inertia $I_q$ reaches a critical value
$I_{cr}$ for an observable, the switching among the different eigenvalues of
that observable stops and the corresponding superposition comes to an end.
Consequently, increasing the mass, temperature, gravitational force, etc. of a
quantum system increases its quantum inertia until the superposition of states
disappears for all the observables and the system transmutes into a classical
one. The process could be reversible: decreasing the size, temperature,
gravitational force, etc. of a classical system one could revert the situation.
Entanglement can only occur between quantum systems, not between a quantum
system and a classical one, because an exact synchronization between the
switchings of the systems involved must be established in the first place and
classical systems do not have any switchings to start with. Future experiments
might determine the critical inertia $I_{cr}$ corresponding to different
observables. In addition, our proposal implies a new radiation mechanism in
strong gravitational fields, giving rise to non-thermal synchrotron emission,
that could contribute to neutron star formation. Superconductivity,
superfluidity, Bose-Einstein condensates, and any other physical phenomena at
very low temperatures must be reanalyzed in the light of this interpretation,
as well as mesoscopic systems in general.
