Exact Symmetries of Electron Interactions in the Lowest Landau Level
  Considering the system of interacting electrons in the lowest Landau level we show that the corresponding four-fermion Hamiltonian is invariant with respect to the local area-preserving transformations. Testing a certain class of interaction potentials, we find that this symmetry is universal with respect to a concrete type of potentials. 
M. Eliashvili, Z. F. Ezawa and G. Tsitsishvili