  While deeply supercooled liquids exhibit divergent viscosity and increasingly
heterogeneous dynamics as the temperature drops, their structure shows only
seemingly marginal changes. Understanding the nature of relaxation processes in
this dramatic slowdown is key for understanding the glass transition. Here, we
show by atomistic simulations that the heterogeneous dynamics of glass-forming
liquids strongly correlate with the local residual plastic strengths along soft
directions computed in the initial inherent structures. The correlation
increases with decreasing temperature and is maximum in the vicinity of the
relaxation time. For the lowest temperature investigated, this maximum is
comparable with the best values from the literature dealing with the
structure-property relationship. However, the nonlinear probe of the local
shear resistance in soft directions provides here a real-space picture of
relaxation processes. Our detection method of thermal rearrangements allows us
to investigate the first passage time statistics and to study the scaling
between the activation energy barriers and the residual plastic strengths.
These results shed new light on the nature of relaxations of glassy systems by
emphasizing the analogy between the thermal relaxations in viscous liquids and
the plastic shear transformation in amorphous solids.
