Biopolymer Networks Mechanics
The elastic response of biological materials is highly nonlinear, exhibiting a strong increase in stiffness with strain. The nonlinear mechanics of the cytoskeletal network inside a cell can be understood on the level of a single fibre . However, despite an abundance of computational studies, there was little insight into the origin of the nonlinear mechanics of extracellular networks and tissues (such as collagen) where thermal fluctuations are relatively insignificant .
Recently, we showed that the development of rigidity in sub-isostatic networks is characterised by a strain-controlled continuous phase transition with signatures of criticality [3-5]. Moreover, the nonlinear mechanics of collagen networks can be quantitatively captured by predictions of scaling theory for controlled critical behaviour over a wide range of network concentrations and strains up to failure of the material. In the last 5 years, we have developed a scaling theory for critical behaviour , studied the effect of criticality on normal stresses  and are currently working on dynamical aspects such as critical slowing down in biopolymer networks.
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