Speaker
Francesco Aprile
(Complutense University of Madrid)
Description
I will consider the theory of n tensor multiplets on AdS3×S3 coupled to six-dimensional (2,0) supergravity. Through the AdS/CFT correspondence, this theory is known to arise from a top-down string construction, which fixes the number of tensor multiplets to n=21. The same value can also be inferred from six-dimensional gravitational anomaly cancellation. In this talk, I will derive n=21 from a different perspective, taking the viewpoint of a low-energy observer in AdS3 who has access, from the bootstrap, to the four-point scattering amplitudes of the lightest Kaluza–Klein mode of the tensor multiplets. Remarkably, requiring this data to be consistent with crossing symmetry singles out n=21, manifesting the string lamppost.