Large phonon time-of-flight fluctuations in expanding flat condensates of cold Fermi gases.

We reexamine how quantum density fluctuations in condensates of ultra-cold Fermi gases lead to fluctuations in phonon times-of-flight, an effect that increases as density is reduced. We suggest that these effects should be measurable in pancake-like (two-dimensional) condensates on their release from their confining optical traps, providing their initial (width/thickness) aspect ratio is suitably large.

The role of causality in tunable Fermi gas condensates.

We develop a new formalism for the description of the condensates of cold Fermi atoms whose speed of sound can be tuned with the aid of a narrow Feshbach resonance. We use this to look for spontaneous phonon creation that mimics spontaneous particle creation in curved space-time in Friedmann-Robertson-Walker and other model universes.

Derivation of hydrodynamics for the gapless mode in the BEC-BCS crossover from the exact one-loop effective action.

We derive generalized two-superfluid continuity equations for the BEC-BCS crossover in the presence of a Feshbach resonance at T=0. In addition, we calculate the velocity of sound throughout both BCS and Bose-Einstein condensation (BEC) regimes.