Poisson solid
= Poisson solid
{c}
{title2=$\lambda=\mu,\quad\nu=1/4,\quad\alpha^2=3\beta^2$}
An isotropic <linear elasticity> material with equal positive <Lamé parameters> has <Poisson's ratio> $1/4$ and the displayed compressional/shear speed ratio. This simplifying model fixes the relative amplitudes in the <tensile-crack radiation pattern>; it does not describe every stable isotropic solid.