Upcoming Events

Unifying Theory for Tuned Critical Quake Statistics: From Compressed Nanopillars to Earthquakes ?

April 17, 2014 11:00AM to 12:00PM
Presenter 
Karin Dahmen, University of Illinois at Urbana Champaign
Location 
Building 241
Type 
Colloquium
Series 
Materials Science Colloquium
This Materials Science Colloquium will take place in the new Energy Sciences Building, ESB 241, Rm. D172.

Abstract:
The deformation of many solid and granular materials is not continuous, but discrete, with intermittent slips similar to earthquakes. Here, we suggest that the statistical distributions of the slips, such as the slip-size distributions, reflect tuned criticality, with approximately the same regular (power-law) functions, and the same tunable exponential cutoffs, for systems spanning 13 decades in length, from tens of nanometers to hundreds of kilometers; for compressed nano-crystals, amorphous materials, sheared granular materials, and earthquakes.

The similarities are explained by a simple analytic model, which suggests that results are transferable across scales. This study provides a unified understanding of fundamental properties of shear-induced deformation in systems ranging from nanocrystals to earthquakes. It also provides many new predictions for future experiments and simulations. The studies draw on methods from the theory of phase transitions, the renormalization group, and numerical simulations. Connections to other systems with avalanches, such as magnets and neuron firing avalanches in the brain are also discussed.