Nature Magazine(Nature 430, 525 - 528 (29 July 2004); doi:10.1038/nature02750) reports:

The nonlinear nature of friction

MICHAEL URBAKH1, JOSEPH KLAFTER1, DELPHINE GOURDON2 & JACOB ISRAELACHVILI2

1 School of Chemistry, Raymond and Beverley Sackler Faculty of Exact Sciences, Tel-Aviv University, Tel-Aviv 69978, Israel
2 Department of Chemical Engineering, University of California at Santa Barbara, Santa Barbara, California 93106, USA

Correspondence and requests for materials should be addressed to M.U. (urbakh@post.tau.ac.il).

Tribology is the study of adhesion, friction, lubrication and wear of surfaces in relative motion. It remains as important today as it was in ancient times, arising in the fields of physics, chemistry, geology, biology and engineering. The more we learn about tribology the more complex it appears. Nevertheless, recent experiments coupled to theoretical modelling have made great advances in unifying apparently diverse phenomena and revealed many subtle and often non-intuitive aspects of matter in motion, which stem from the nonlinear nature of the problem.