The classical porous media equation is
$$u_t - \Delta(u^m) = 0 \quad m>1.$$
Has the (degenerate) wave equation $$u_{tt} - \Delta(u^m) = 0$$ been subject of studies? What would the physical interpretation of such a wave equation be?
The classical porous media equation is
$$u_t - \Delta(u^m) = 0 \quad m>1.$$
Has the (degenerate) wave equation $$u_{tt} - \Delta(u^m) = 0$$ been subject of studies? What would the physical interpretation of such a wave equation be?