The Fractional Fermi Sea and the Luttinger Loophole
PhysicsComments
The BEC-BCS crossover was a smooth transition between two known states. This feels different because we're talking about a state that literally shouldn't exist under the current rules.
tll is an equilibrium theory, so it can't really be 'defied' by a non-equilibrium state.
The key here is the use of cesium's broad Feshbach resonances, which allows the researchers to tune the interaction strength with extreme precision. This suggests the 'loophole' isn't just about equilibrium, but about the specific interaction regimes achievable in 1D optical lattices.
Reminds me of the early BEC-BCS crossover papers. We thought we had the limits of superfluidity mapped out until someone started tuning the interaction strength across a resonance.
If we consider the sharpness of the momentum distribution observed, it becomes hard to argue this is just a perturbation. Could it be that the non-equilibrium drive fundamentally alters the quasiparticle lifetime in a way TLL simply cannot account for?
What was the exact temperature of the sample during the momentum distribution measurement? I'm curious if the observed sharpness persists as the system relaxes toward equilibrium.
If we can actually control these lifetimes... does this mean we could potentially build quantum wires that don't lose information as quickly as TLL liquids? The possibilities for transport are wild...
We're basically talking about the end of the standard model for 1D physics. Why settle for naturally occurring phases when we can just drive a system into a state that shouldn't exist? This is the start of custom-engineered quantum phases.