Friction at the Microscopic Level Is Shockingly Strong

Here’s the rub with friction: scientists don’t really know how it works. Sure, humans have been harnessing the power of friction since rubbing two sticks together to build a fire, but the physics of friction remains largely in the dark.

"Before this research, we didn't have a good way of controlling or understanding friction," Zvonomir Dogic says. "We still have a lot more to understand but now, one of our oldest sciences is becoming less opaque." Zokru/Istock/Thinkstock

Here’s the rub with friction: scientists don’t really know how it works. Sure, humans have been harnessing the power of friction since rubbing two sticks together to build a fire, but the physics of friction remains largely in the dark.

In a new paper in Nature Materials, Brandeis University professor Zvonomir Dogic and his lab explored friction at the microscopic level. They discovered that the force generating friction is much stronger than previously thought.

Dogic and his team focused on the frictional forces of actin filaments, essential cellular building blocks responsible for many biological functions including muscle contraction, cell movement, and cell division.

All of these processes require filaments to move and slide against one another, generating friction. Scientists assumed that the frictional forces of these movements were minimal, acting more like weaker hydrodynamic friction—like pulling an object through water—than the larger solid friction—pushing an object across a desk.

But they observed the opposite.

We still have a lot more to understand but now, one of our oldest sciences is becoming less opaque.