Brittle fracture down to femto-Joules — and below

I found an interesting paper on the arXiv website that may interest some mechanicians.  Markus

Title:  Brittle fracture down to femto-Joules — and below

Authors: J. Astrom, P.C.F. Di Stefano, F. Probst, L. Stodolsky, J. Timonen 

Abstract: We analyze large sets of energy-release data created by stress-induced brittle fracture in a pure sapphire crystal at close to zero temperature where stochastic fluctuations are minimal. The waiting-time distribution follows that observed for fracture in rock and for earthquakes. Despite strong time correlations of the events and the presence of large-event precursors, simple prediction algorithms only succeed in a very weak probabilistic sense. We also discuss prospects for further cryogenic experiments reaching close to single-bond sensitivity and able to investigate the existence of a transition-stress regime.

URL:  http://arxiv.org/abs/0708.4315