## Transport coefficients

### Set

 context $n,u,Q,T,\mathrm{P},K$ … density, mean velocity, heat flux, pressure tensor, temperature, external force
 definiendum $\langle D,\kappa,p,\eta,\zeta \rangle$

These are matrices or numbers, and they might even depend on any other quantities.

 postulate $u = - D\ \frac{\nabla n}{n}$
 postulate $Q = - \kappa\ \nabla T$
 range $\Lambda_{ik} = \frac{1}{2}\left( \frac{\partial}{\partial x_k}u_i + \frac{\partial}{\partial x_i}u_k \right)$ postulate $P = p\ I - 2\ \eta\ \Lambda - (\zeta+\frac{2}{3}\eta)\ \nabla u$
 postulate $u = \mu\ K$