Measuring interface tensions in 4d SU(N) lattice gauge theories

We propose a new algorithm to compute the order-order interface tension in SU(N) lattice gauge theories. The algorithm is trivially generalizable to a variety of models, e.g., spin models. In the case N = 3, via the perfect wetting hypothesis, we can estimate the order-disorder interface tension. In the case N = 4, we study the ratio of dual k-tensions and find that it satisfies Casimir scaling down to T = 1.2 T-c.