  It is notorious that quantum mechanics (QM) cannot predict well-defined
values for all physical quantities. Less well-known, however, is the fact that
QM is unable to furnish probabilistic predictions even in emblematic scenarios
such as the double-slit experiment. In contrast, equipped with postulate
trajectories, Bohmian mechanics (BM) has inherited more predictive power. It
follows that, contrary to common belief, QM and BM are not just different
interpretations but distinct theories. This work formalizes the aforementioned
assertions and illustrates them through three case studies: (i) free particle,
(ii) free fall under a uniform gravitational field, and (iii) the double-slit
experiment. Specifically, we introduce a prescription for constructing a
flight-time probability distribution within generic trajectory-equipped
theories. We then apply our formalism to BM and derive probability
distributions that are unreachable by QM. Our results can, in principle, be
tested against real experiments, thereby assessing the validity of Bohmian
trajectories.
