  We consider the classical concept of time of permanence and observe that its
quantum equivalent is described by a bona fide self-adjoint operator. Its
interpretation, by means of the spectral theorem, reveals that we have to
abandon not only the idea that quantum entities would be characterizable in
terms of spatial trajectories but, more generally, that they would possess the
very attribute of spatiality. Consequently, a permanence time shouldn't be
interpreted as a "time" in quantum mechanics, but as a measure of the total
availability of a quantum entity in participating to a process of creation of a
spatial localization.
