Non-Locality in the Similarity Renormalization Group

The Similarity Renormalization Group (SRG) is a continuous series of unitary transformations that can be implemented as a flow equation. Nuclear forces softened by SRG are inherently non-local. Further SRG will induce higher-body forces even when they are not present in the initial Hamiltonian. By exploiting simple integral projections, the non-local nuclear two-body forces can be separated into a local interaction and non-local residual. This residual is demonstrated to be perturbative at low energy, raising the possibility of using non-local interactions with modern quantum Monte Carlo methods. The results of this separation and the status on development of tools, such as hyper-spherical plane wave SRG evolution for the three nucleon force, for doing similar projections to the three and four nucleon force will be presented.