On cloaking for elasticity and physical equations with a transformation invariant form

@article{Milton2006OnCF,
  title={On cloaking for elasticity and physical equations with a transformation invariant form},
  author={Graeme W. Milton and Marc Briane and J. R. Willis},
  journal={New Journal of Physics},
  year={2006},
  volume={8},
  pages={248-248}
}
In this paper, we investigate how the form of the conventional elastodynamic equations changes under curvilinear transformations. The equations get mapped to a more general form in which the density is anisotropic and additional terms appear which couple the stress not only with the strain but also with the velocity, and the momentum gets coupled not only with the velocity but also with the strain. These are a special case of equations which describe the elastodynamic response of composite… 

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