Soft Matter Seminar: Rachel Glade

The Syracuse University Department of Physics is pleased to welcome Rachel Glade, Assistant Professor of Earth and Environmental Sciences and Mechanical Engineering at the University of Rochester, for this week’s Soft Matter Seminar.

“From Icy Soil Drips to Rivers of Brazil Nuts: Connections between Earth’s landscapes and everyday materials”

Earth and planetary surfaces are home to some of the most complex soft materials in existence; for example, typical soil or river sediment is composed of a heterogeneous mixture of fluids, organic matter, and sticky sediment grains with different shape and size. Sediment transport dynamics result in striking landscape patterns that exist at time and length scales well beyond those typically studied in Materials Science. Here we explore connections between patterns on Earth’s surface and everyday materials, focusing on the complicating roles of 1) cohesion and 2) grain shape. First, we use remote sensing and a theoretical scaling analysis to show that large, slow-moving soil patterns in Arctic regions and on Mars may be analogous to surface-tension dominated fluid instabilities like paint drips, with implications for our understanding of pattern development and dynamics in cohesive granular media. Next, we use numerical models to explore the role of grain shape in granular segregation processes that occur in rivers, landslides and other geophysical flows as well as industrial applications. We hope to show that drawing connections between sediment dynamics and Soft Matter Physics can inform not only our understanding of planetary surfaces, but also materials in general.