  We observe that the yield strength of a variety of materials, including
highly structured and densely packed metals, alloys and semi-crystalline
polymers is reasonably approximated by the thermal energy density of the
material. This suggests that it is related to the entropic cost of the
irreversible work done during plastic deformation rather than the enthalpic
cost that depends on the elastic modulus of the material. Here we propose that
the entropic cost of material rearrangement in crystalline solids arises from
the difference in the uncertainty in building block positions before and after
yielding and estimate it using Landauer's principle for information processing.
The yield strength thus obtained in given by the thermal energy density of the
material multiplied by ln(2) and provides a guidepost in estimating the
strength of materials complementary to the "theoretical strength of solids".
