MIT researchers explain why fingers, raisins, and brains wrinkle
In new paper published in the journal Nature Materials (PDF), researchers at MIT conceptualize a mathematical equation to explain the nature of wrinkling.
“If you look at skin, there’s a harder layer of tissue, and underneath is a softer layer, and you see these wrinkling patterns that make fingerprints,” says MIT assistant professor of mathematics Jörn Dunkel. “Could you, in principle, predict these patterns? It’s a complicated system, but there seems to be something generic going on, because you see very similar patterns over a huge range of scales.”
The team verified their equation by testing centimeter-wide soft hemispheres made of silicone materials. The wrinkling they saw matched their equation, but with differences arising from coefficient variables such as the curve of the surface, the strength of the wrinkling force, and the strength of the object’s skin.
These findings may help biologists understand wrinkling patterns in biology and could also help chemists to perfect the microscopic lenses that go into digital imaging technologies.