Persistence of quantum violation of macrorealism for large spins even under coarsening of measurement times.

We investigate the effect of coarsening of measurement times on the quantum violation of macrorealism (MR) for multilevel spin systems under coarse-grained measurements for which individual outcomes cannot be unambiguously discriminated and measurement times also have experimental indeterminacy. In our treatment, along with different measurement outcomes being clubbed together into two groups in order to model the coarse-grained measurements, 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 MR 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 MR 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.