  We investigate quantum violation of macrorealism for multilevel spin systems
under the condition of coarsening of measurement times -- i.e., when
measurement times have experimental indeterminacy. This is studied together
with the effect of coarsening of measurement outcomes for which individual
outcomes cannot be unambiguously discriminated. In our treatment, along with
different measurement outcomes being clubbed together into two groups in order
to model the coarsening of measurement outcomes, importantly, varying degrees
of coarsening of measurement time intervals have also been considered. This
then reveals that while for a given dimension, the magnitude of quantum
violation of macrorealism decreases with the increasing degree of coarsening of
measurement times, interestingly, this effect of coarsening of measurement
times can be annulled by increasing the dimension of the spin system so that in
the limit of large spin, the quantum violation of macrorealism continues to
persist. Thus, the result obtained demonstrates that classicality for large
spins does not emerge from quantum mechanics in spite of the coarsening of
measurement times.
