  Most materials exhibit creep memory under the action of a constant load. The
memory behavior is governed by Andrade's creep law, which also has an inherent
connection with the Omori-Utsu law of earthquake aftershocks. Both empirical
laws lack a deterministic interpretation. Coincidentally, the Andrade law is
similar to the time-varying part of the creep compliance of the fractional
dashpot in anomalous viscoelastic modeling. Consequently, fractional
derivatives are invoked, but since they lack a physical interpretation, the
physical parameters of the two laws extracted from curve fit lack confidence.
In this Letter, we establish an analogous linear physical mechanism that
underlies both laws and relates its parameters with the material's macroscopic
properties. Surprisingly, the explanation does not require the property of
viscosity. Instead, it necessitates the existence of a rheological property
that relates strain with the first order time derivative of stress, which
involves jerk. Further, we justify the constant quality factor model of
acoustic attenuation in complex media. The obtained results are validated in
light of the established observations.
