Krill Prize 2014
Dr. Eran Bouchbinder (ד”ר ערן בוכבינדר)
Physics of comple out-of-equilibrium systems, materials physics and mechanics.
The Bouchbinder group is a theoretical condensed-matter and materials physics group interested in non-equilibrium, driven, phenomena related to the deformation, flow and failure of materials and interfaces. Our research program addresses some long-standing problems in modern solid mechanics, materials science, biophysics and geophysics from statistical and condensed-matter physics perspectives. The physical problems of interest are typically characterized by a rather unique coupling between widely separated time and length scales, where the major intellectual challenge is to build conceptual and mathematical bridges that allow to understand how collective, complex, microscopic processes give rise to the emergence of a wealth of macroscopic behaviors. Examples include the nearly singular localized region near the tip of a crack that controls the strength and structural integrity of a macroscopic piece of material, the accumulation of intermittent, inhomogeneous, microscopic particle rearrangements in a disordered/glassy solid that determines its macroscopic plastic response, the collective dynamics of micron-scale contact asperities that control the physics of spatially extended frictional interfaces and molecular mechanisms that control the large scale cellular response to the mechanical environment. Our ultimate goal is to develop quantitatively predictive continuum theories that can be used in a wide range of problems and to elucidate basic physical questions related to them.
While our basic motivation is that of theoretical physics, thriving to obtain a fundamental understanding of generic phenomena, we rarely study toy models. Instead, we insist on closely looking at extensive experimental data and realistic computer simulations, with the aim of developing quantitative continuum level understanding of the phenomena of interest and generating testable predictions. This entails close collaborations with experimental and simulational groups, which complement and greatly enrich our theoretical efforts. In the last few years we made several contributions to the theory of dynamic fracture, non-equilibrium thermodynamics of driven solids, the theory of plasticity, the theory of sliding friction and the theory of cellular mechanosensitivity. The main achievements include, among others, a basic understanding of a rapid fracture instability as linked to a new intrinsic length scale associated with near crack tip nonlinearities, developing a unified framework for understanding the linear response of soft and hard glassy materials, a novel prediction of a ductile-to-brittle transition in metallic glasses based on our effective temperature thermodynamic theory, suggesting a novel explanation of the existence of slow sliding modes at frictional interfaces and a novel approach to cell reorientation dynamics.
Ongoing research spans a broad range of projects and collaborative efforts (national and international, including theoretical, experimental and computational groups), expanding already developed topics in the group and exploring new research directions, such as dislocation-mediated crystal plasticity, the mechanics of nanocomposite materials and cell mechanics. Making theoretical progress in all of these problems will lead to a better understanding of natural/existing manmade materials and potentially facilitate the quest for new materials, a major issue of prime scientific, technological and economic importance.