Plastic deformation: Shearing mountains atom by atom

► Rocks, wood, ceramics, semiconductors, and metals all deform in the same way, namely by heterogeneous shear banding via hierarchical orthogonal shear modes. ► While the governing principles of deformation are the same for rocks, wood, ceramics, semiconductors, and metals, these materialsdiffer in their microscopic deformation mechanisms and in the width of the shear band, which covers twelve orders of magnitude from angstroms to hundreds of meters. ► Microscopic deformation mechanisms couple to macroscopic deformation mechanisms, i.e. shear banding, through the collective properties of defect groups on the mesoscale.