Towards holographic walking from $\mathcal{N} = 4$ super Yang-Mills

Abstract

We propose that a holographic description of ‘walking’ behavior, namely quasi-conformal dynamics relevant for technicolor models, can be obtained from relevant deformations of $\mathcal{N} = 4$ super Yang-Mills. We consider deformations which drive the theory close to the $\mathcal{N} = 1$ Leigh-Strassler fixed point, eventually deviating from it in the deep IR. We use the Pilch-Warner dual supergravity description of the flow between the $\mathcal{N} = 4$ and the $\mathcal{N} = 1$ fixed points to focus on observables that only require knowledge of the walking region. These include large anomalous dimensions of quark bilinear operators, which we study via probe D7-branes. We also make a first attempt at describing the theory beyond the walking region by introducing an infrared cut-off, in the spirit of hard-wall models. In this case we find a light, dilaton-like scalar state, but whether this mode persists in the exact theory remains an open question.