Superfluid Pairing in Neutrons and Cold Atoms

Ultracold atomic gases and low-density neutron matter are unique in that they exhibit pairing gaps comparable to the Fermi energy which in this sense are the largest in the laboratory and in nature, respectively. This strong pairing regime, or the crossover between BCS and BEC regimes, requires non-perturbative treatments. We describe Quantum Monte Carlo results useful to understand the properties of these systems, including infinite homogeneous matter and trapped inhomogeneous gases.