Critical dynamics of Heisenberg fluids at the gas-liquid transition

We derive the static and dynamical model describing the critical statics an d dynamics of a Heisenberg fluid in a magnetic field near its gas-liquid cr itical point. It turns out that the model is equivalent to the one describi ng a liquid mixture near its plait point Using the results known for that c ase we predict the critical behavior of the liquid and magnetic transport c oefficients and the velocity and absorption of the sound mode.