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Non-Hookean Elasticity of 2D Model Tissue

ORAL

Abstract

We study the peculiar mechanical response of a mean-field approximation to the vertex model (VM) of 2D epithelia. In the absence of T1 rearrangements, the VM exhibits a transition between a soft and a stiff solid tuned by the target shape index of the cells and is associated with the onset of geometric incompatibility. By examining the response to a variety of deformations, we show that the stiff-solid phase exhibits nonlinear elastic response that cannot be recast in the framework of conventional Hookean elasticity, even in the limit of infinitesimal strain. Instead, the linear mechanical response, when allowing shape change, depends on the specific protocol used for the imposed deformation and is not therefore fully characterized by two independent elastic moduli, as in the linear elasticity of a 2D isotropic solid. Our numerical simulations lend support to these conclusions.

Presenters

  • Arthur Hernandez

    University of California, Santa Barbara

Authors

  • Arthur Hernandez

    University of California, Santa Barbara

  • M Cristina Marchetti

    University of California, Santa Barbara, Department of Physics, University of California, Santa Barbara, Department of Physics, University of California, University of California Santa Barbara

  • Mark J Bowick

    University of California, Santa Barbara, Kavli Institute for Theoretical Physics, KITP, University of California, Santa Barbara, University of California Santa Barbara

  • Michael Moshe

    Hebrew University, The Racah Institute of Physics, Hebrew University of Jerusalem

  • Michael F Staddon

    University College London, University Collage London, Physics, University College London