First-order phase transitions in non-equilibrium systems: New perspectives

First-order irreversible phase transitions (IPT's) between an active regime and an absorbing state are studied in two models by means of both simulations and mean-field stability analysis. Hysteresis around coexistence is the result of the interplay of the length of the interface, its curvature, and a memory effect related to the phase which is being removed. A controversy on the occurrence of scale-invariance is clarified, conciliating the behavior of IPT's with its reversible counterpart.