  We present theoretical findings on the spin collective modes of a two-species
Fermi liquid, prepared alternatively in a polarized equilibrium or a polarized
non-equilibrium state. We explore the effects on these modes of a diverging
s-wave scattering length, as occurs near a Feshbach resonance in a Fermionic
atomic gas. We compare these atomic gas modes with those of the conventional
Helium-3 system, and we find that they differ from the conventional systems,
and that the gap and spin stiffness are tunable via the Feshbach resonance.

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