1,100 Words

Magnetic Webs

Sand, snow and other granular materials have a split personality; they can flow through your fingers like a liquid, but if you squeeze them too hard, they “jam,” becoming firm like a solid. Engineers would like to harness this dual nature to create flexible scaffolds for soft robotics or buildings – but first, they must learn to control their behavior. Using transparent beads, researchers in Robert Behringer’s lab investigated how jamming changes when some particles in a material are magnetized. They found that magnetic particles self-organize into a web, shown here with blue lines, which makes the material more stable. Read the paper here. (Credit: Jonathan Barés)