Γ-CONVERGENCE OF GRAPH GINZBURG-LANDAU FUNCTIONALS

We study Gamma-convergence of graph-based Ginzburg-Landau functionals, both the limit for zero diffusive interface parameter epsilon -> 0 and the limit for infinite nodes in the graph m -> infinity. For general graphs we prove that in the limit epsilon -> 0 the graph cut objective function is recovered. We show that the continuum limit of this objective function on 4-regular graphs is related to the total variation seminorm and compare it with the limit of the discretized Ginzburg-Landau functional. For both functionals we also study the simultaneous limit epsilon -> 0 and m -> infinity, by expressing epsilon as a power of m and taking m -> infinity. Finally we investigate the continuum limit for a nonlocal means-type functional on a completely connected graph.