“…Nevertheless, it should be pointed out that important progresses have been achieved for the original Ericksen-Leslie model (as well as its simplified versions), in which the penalisation energy density W (d) is removed and instead, a Lagrangian multiplier corresponding to the unitary constraint |d(t, x)| = 1 has to be introduced in the director equation. For instance, we refer the interested readers to [7,23,24,27,29,33,39,44,49] for the simplified liquid crystal system involving the transported heat flow of harmonic map, to [21,26,32,45] for the general Ericksen-Leslie system as well as its non-isothermal extension [12], and to [2,28] for the case with inertial term in the director equation (i.e., the so-called hyperbolic Ericksen-Leslie system).…”