Applied graph theory? I don't have access to full article so I can't tell if it's actual math or something more hand-wavy stuff.
This is just an example of a well-known recent sociology paper that can appeal to science-minded people unfamiliar with sociology.
By the way, it's a danger to rely too much on mathematical formalism as a heuristic for deciding whether a research field is scientific or valid. String theory for example lacks empirical evidence (and maybe even the possibility of empirical validation altogether).