Author(s): Jacob F. Steiner, Felix von Oppen, and Reinhold Egger Quantum many-body systems coupled to out-of-equilibrium reservoirs can behave as active matter and exhibit signs of flocking. However, the resulting steady states are highly mixed and carry only weak quantum signatures. We show that signatures of active matter also arise in ensembles of pure states … [Phys. Rev. Lett. 137, 120403] Published Wed Sep 16, 2026