Green-Lagrange strain tensor
= Green-Lagrange strain tensor
{c}
{title2=$E^{(2)}=(F^TF-I)/2$}
With the <right Cauchy-Green deformation tensor> $C=F^TF$, the <Green-Lagrange strain tensor> measures the change in the material metric. Since $\dot E^{(2)}=F^TDF$, its <work-conjugate stress and strain> partner is the <second Piola-Kirchhoff stress tensor> $F^{-1}\tau F^{-T}$. The formula follows by cycling factors in $T:\dot E^{(2)}$, not by identifying nominal and symmetric material stress.