  We present an effective field theory for high density, low temperature QCD in
the crystalline colour superconductive phase (LOFF phase). This interesting
phase of QCD is characterized by a gap parameter with a crystalline pattern,
breaking traslational and rotational invariance, and could have astrophysical
applications. In the effective theory the fermions have a Majorana mass, which,
besides colour, breaks translation and rotation symmetries. Fermions couple to
the three phonons arising from the breaking of rotation and translation
invariance. Integrating out the fermions leads eventually to an effective
lagrangian in terms of the phonon fields only, which satisfies an anisotropic
dispersion relation.
