Vanessa Robins (11/28/17): Persistence diagrams of bead packings

Uncovering grain-scale mechanisms that underlie the disorder-order transition in assemblies of granular materials is a fundamental problem with technological relevance. To date, the study of granular crystallization has mainly focussed on the symmetry of crystalline patterns while their emergence and growth from irregular clusters of grains remains largely unexplored. Here crystallization of three-dimensional packings of frictional spherical beads is studied at the grain-scale using X-ray tomography and persistent homology. The persistence diagram encodes new information on the formation process of tetrahedral and octahedral pores, the building blocks of crystalline close-packed spheres. Four key formation mechanisms of these pores reproduce the main changes of the map during crystallization and provide continuous deformation pathways representative of the crystallization dynamics.

Видео Vanessa Robins (11/28/17): Persistence diagrams of bead packings канала Applied Algebraic Topology Network