hopefully the theoretical improvements represent at least a moral victory. In any case one would naively have expected errors of order a few 100% in all of these models so the closeness to QCD across a range of holographic models supports the robustness of the approach. A drawback of these models to date has been that the geometry returns to AdS for large r , meaning that the field theory is not asymptotically free in the UV. Incorrect physics in the UV may affect the strong coupling regime in the IR [144]. Here we investigated corrections to the matching of the 5D gauge coupling to naive perturbative QCD results. We found that this coupling’s value should be changed at the 18% level indicating the size of non-perturbative effects. In the future one might hope to study the importance of higher dimension operators in the IR physics as well. 96