The maximum entropy principle is applied to the formal derivation of
isothermal, Euler-like equations for semiclassical fermions (electrons and
holes) in graphene. After proving general mathematical properties of the
equations so obtained, their asymptotic form corresponding to significant
physical regimes is investigated. In particular, the diffusive regime, the
Maxwell-Boltzmann regime (high temperature), the collimation regime and the
degenerate gas limit (vanishing temperature) are considered.Comment: 32 pages, 2 figure
