1:30 pm VIA ZOOM
Engineering Peturbative String Duals for Symmetric Product Orbifold CFTs.
50 years ago, ‘t Hooft observed that in U(N) gauge theories ``the topological structure of the perturbation series in 1/N is identical to that of the dual models’’ (string theories). Maldacena’s AdS/CFT correspondence provides concrete realizations, yet these are famously non-perturbative in the gauge coupling. In my talk I will address the problem of constructing perturbative string duals. If this could be done systematically, it would not only open the door for proofs of the AdS/CFT correspondence but could also provide novel examples of string duals with and without supersymmetry. Here I shall discuss one particular class of examples in which the CFTs are some marginal perturbations of symmetric product orbifolds in two dimensions. From their correlation functions one can indeed engineer bosonic string theories whose amplitudes may be shown to reproduce the CFT correlation function order-by-order both in the coupling and in 1/N. The proofs do not require to compute and compare correlation functions explicitly but rather relies on a sequence of identities that can be derived using path integral methods.