Multiparticle Flux-Tube S-matrix Bootstrap

We introduce the notion of jets, states of collinear flux-tube excitations. We argue for the analyticity, crossing, and unitarity of the multiparticle scattering of these jets and, through the S-matrix bootstrap, place bounds on a set of finite-energy multiparticle sum rules. Such bounds define a matrioska with a smaller and smaller allowed regions as we impose more constraints. The Yang-Mills flux tube, as well as other interesting flux-tube theories recently studied through lattice simulations, lie inside a tiny island hundreds of times smaller than the most general space of allowed theories.