Lagrangian reductions and integrable systems in condensed matter
  We consider a general approach for the process of Lagrangian and Hamiltonian reduction by symmetries in chiral gauge models. This approach is used to show the complete integrability of several one dimensional texture equations arising in liquid Helium phases and neutron stars. 
Fran\c{c}ois Gay-Balmaz, Michael Monastyrsky, Tudor S. Ratiu
math.DS cond-mat.other