  We exploit the analogy with the quantum Hall (QH) effect for electrons to
study the possible atomic QH states of a rapidly-rotating Bose-Einstein
condensate. Actually, there is a nearly perfect map of the present problem in
the QH regime to the QH physics for electrons. The profound map enables one to
give a physically appealing definitions of the filling fraction and the "atomic
Hall conductance" that is quantized for atomic Laughlin states. This
quantization might imply an exotic fractionalization of atomic mass. We also
briefly discuss an effective Chern-Simons theory for describing the atomic QH
liquids where a gravitational-like field naturally emerges.
