  The definition of a length operator in quantum cosmology is usually
influenced by a~quantum theory for gravity considered. The semiclassical limit
at the Planck age must meet the requirements implied in present observations.
The features of a semiclassical wave-functional state are investigated, for
which the modern measure(ment)s is consistent. The results of a length
measurement at present times are compared with the same measurement operation
at cosmological times. By this measure, it is possible to discriminate, within
the same Planck-length expansion, the corrections to a Minkowski flat space
possibly due to classicalization of quantum phenomena at the Planck time and
those due to possible quantum-gravitational manifestations of present times.
This~analysis and the comparison with the previous literature can be framed as
a test for the verification of the time at which anomalies at present related
to the gravitational field, and, in particular, whether they are ascribed to
the classicalization epoch. Indeed, it allows to discriminate not only within
the possible quantum features of the quasi (Minkowski) flat spacetime, but also
from (possibly Lorentz violating) phenomena detectable at high-energy
astrophysical scales. The results of two different (coordinate) length measures
have been compared both at cosmological time and as a perturbation element on
flat Minkowski spacetime. The differences for the components of the
corresponding classical(ized) metric tensor have been analyzed at different
orders of expansions. The comparison of the results of (straight) length
measures in two different directions, in particular, can encode the pertinent
information about the parameters defining the semiclassical wavefunctional for
(semiclassicalized) gravitational field.
