Holon Physics Seminar 24.1.17

 

 

---

 

Friction is generally described by a single degree of freedom, a ‘friction coefficient’. We experimentally study the space-time dynamics of the onset of dry and lubricated frictional motion when two contacting bodies start to slide.

 

We first show that the transition from static to dynamic sliding is governed by earthquakes. Moreover, the structure of both these “laboratory earthquakes” as well as the real thing is quantitatively described by singular solutions describing the motion of rapid cracks.

 

We demonstrate that this framework quantitatively describes both earthquake motion and arrest. A further surprise is that lubricated interfaces, although “slippery”,  actually becomes tougher; lubricants significantly increase dissipated energy during rupture. The results establish a new (and fruitful) paradigm for describing friction.