NEUTRAL FERMIONS AT FILLING FACTOR NU=1 2

We present a particle-hole symmetric theory for a two-dimensional elec tron gas at filling factor nu = 1/2. In this theory, elementary excita tions are dipolelike fermions floating on top of the nu = 1/2 boson qu antum-Hall liquid. In the absence of disorder these dipoles can form a Fermi liquid. Disorder can break them apart and drive the ground stat e into a quantum critical state.