Quantum advantage by designing beneficial dissipation from lossless dynamics

arXiv:2610.38183v1 Announce Type: new Abstract: Passive loss removes probability from a system and therefore seems unable to improve an unconditional target. This intuition is exact for classical population dynamics under sink-only removal: passive killing obeys a finite-strength monotonicity principle even after optimization over the remaining controls. Here we show that coherent quantum dynamics can violate this classical monotonicity because coherent contributions to the final target can interfere destructively. We derive a trajectory-level criterion that determines when such a detrimental contribution is physically accessible to passive loss and accumulates into a net unconditional benefit.