DISORDER AND COMPLEXITY IN AN IDEAL NONEQUILIBRIUM FERMI GAS

A model of a non-equilibrium ideal Fermi gas has been devised which is simple enough to be treated analytically. Its properties are compared with a matching equilibrium gas and functions for ''disorder'' and '' complexity'' are defined and evaluated. The non-equilibrium entropy in creases with ''order'' up to a certain particle number. Beyond this, t he system reverts to the more usual behaviour of entropy increasing wi th ''disorder''. But this tendency is only slight in this model. (C) 1 998 Elsevier Science B.V.