Interaction expansion inchworm Monte Carlo

We generalize the inchworm Monte Carlo framework for the interaction expansion. Inchworm Monte Carlo is a method to iteratively group and sample classes of diagrams in diagrammatic perturbation expansions. In the hybridization expansion, the inchworm was shown to drastically delay the onset of the sign problem. Here, we generalize the iterative procedure to the interaction expansion and show application to multi-orbital quantum impurity models with general interaction and hybridization. We clarify convergence properties and highlight similarities and differences to the bare and bold Monte Carlo methods.