A stroll on the beach can mean sinking your toes into smooth sand or walking firm-footed on a surface that appears almost solid. While both properties are commonplace, exactly what it is that makes ...

Examples of granular matter: multicolored plastic balls in a playground, gravel, sesame seeds and lentils (clockwise from top left). Images by Julia Kertesz, Martin Olsson, Jitender Kumar and Zyance ...

Dense flows of grains driven by gravity down inclines occur in nature and in industrial processes. Natural examples include rock avalanches and dune slides. Applications are found in the chemical, ...

Pour sand from a bucket and it flows like a liquid, but stand on it and it supports weight like a solid. This unusual behavior is a property of granular materials, and it is one of the reasons ...