  Plastic deformation of crystals is a physical phenomenon, which has immensely
driven the development of human civilisation since the onset of the
Chalcolithic period. This process is primarily governed by the motion of line
defects, called dislocations. Each dislocation traps a quantum of plastic
deformation expressible in terms of its Burgers vector[1,2]. Theorising the
mechanisms of dislocation motion at the atomistic scales of length and time
remains a challenging task on account of the extreme complexities associated
with the dynamics. We present a new concept of modelling a moving dislocation
as the dynamic distribution of the elastic field singularity within the span of
the Burgers vector. Surprisingly, numerical implementation of this model for
the periodic expansion-shrinkage cycle of the singularity is found to exhibit
an energetics, which resembles that of a dislocation moving in the presence of
the Peierls barrier[1-4]. The singularity distribution is shown to be the
natural consequence under the external shear stress. Moreover, in contrast to
the conventional assumption, here the calculations reveal a significant
contribution of the linear elastic region surrounding the core towards the
potential barrier.
