Abstract:
I will describe the application of coupled cluster theory to model systems of metallic solids and cold-atom gases. After giving a brief overview of coupled cluster theory, I will evaluate the accuracy of several cost-saving approaches in estimating the CCSD correlation energy for a model metallic system, the uniform electron gas, in the complete basis set and thermodynamic limits. I will then present calculations of the spectral function of the uniform electron gas in these same limits, the results of which are rationalized by applying a bosonized coupled-cluster theory to an approximate, simplified Hamiltonian that couples plasmons to a structureless core hole state. Finally, I will show how coupled-cluster theory captures the many-body nature of two-component Fermi gases with tunable, attractive interactions.