Challenges to observation of many-body localization

Many-body localization (MBL) freezes the dynamics of a disordered quantum interacting system, inhibiting thermalization and resulting in persistent memory initial state. Here, with help extensive numerical simulations, authors find slow decay imbalance, quantity often employed experimental studies MBL, even though disorder strength considerably exceeds current estimates position MBL transition. This suggests approach to thermal equilibrium identifies challenges for unequivocal demonstrations MBL.