  Although recent theoretical and experimental progress have considerably
clarified pairing mechanisms in spin 1/2 fermionic superfluid with equally
populated internal states, many open questions remain when the two spin
populations are mismatched. We show here that, taking advantage of the
universal behavior characterizing the regime of infinite scattering length, the
macroscopic properties of these systems can be simply and quantitatively
understood in the regime of strong interactions.
