Multifluid magnetohydrodynamic turbulence in weakly ionised
  astrophysical plasmas
  Initial results from simulations of 4-fluid MHD turbulence in molecular
clouds are presented. The species included in the simulations are ions,
electrons, negatively charged dust grains and neutrals. The results indicate
that, on length scales of a few tenths of a parsec, multifluid effects have a
significant impact on the properties of the turbulence. In particular, the
power spectra of the velocity and magnetic fields are significantly softened,
while the PDF of the densities of the charged and neutral fluids are
appreciably different. Indeed, the magnetic field strength displays much less
spatial structure on all lengthscales up to 1 pc than in the ideal MHD case.
The assumptions of ideal MHD therefore appear to be inadequate for simulating
turbulence in molecular clouds at these length scales.
