We consider a particular class of solutions of the Boltzmann equation, known as homoenergetic solutions, which are useful to
describe the dynamics of Boltzmann gases under shear, expansion or compression in nonequilibrium situations.
While their well posedness theory has many similarities with the theory of homogeneous solutions of the Boltzmann equation, their
long time asymptotics differs completely, due to the fact that these solutions describe far from equilibrium phenomena. Indeed,
the long time asymptotics cannot always be described by Maxwellian distributions. For several collision kernels the asymptotics of
homoenergetic solutions is given by particle distributions which do not satisfy the detailed balance condition.
In this talk I will describe different possible long time asymptotics of homoenergetic solutions of the Boltzmann equation, as
well as some open problems in this direction. (This is a joint work with R.D.James and J.J.L.Velázquez).