Elasticity tensor
= Elasticity tensor
{title2=$C_{ijkl}$}
The <elasticity tensor> relates <stress> to infinitesimal <strain> by $\sigma_{ij}=C_{ijkl}\epsilon_{kl}$. In conservative <linear> elasticity, the minor symmetries reflect symmetric <stress> and <strain>, while the major symmetry $C_{ijkl}=C_{klij}$ expresses the existence of an elastic energy <density>.