Slip avalanches in metallic glasses and granular matter reveal universal dynamics

Universality in materials deformation is of intense interest: universal scaling relations if exist would bridge the gap from microscopic deformation to macroscopic response in a single material-independent fashion. While recent agreement of the force statistics of deformed nanopillars, bulk metallic glasses, and granular materials with mean-field predictions supports the idea of universal scaling relations, here for the first time we demonstrate that the universality extends beyond the statistics, and applies to the slip dynamics as well. By rigorous comparison of two very different systems, bulk metallic glasses and granular materials in terms of both the statistics and dynamics of force fluctuations, we clearly establish a material-independent universal regime of deformation. We experimentally verify the predicted universal scaling function for the time evolution of individual avalanches, and show that both the slip statistics and dynamics are universal, i.e. independent of the scale and details of the material structure and interactions. These results are important for transferring experimental results across scales and material structures in a single theory of deformation.