Non-invertible symmetries in SN orbifold CFTs and holography

We study non-invertible defects in two-dimensional SN orbifold CFTs. We construct universal defects which do not depend on the details of the seed CFT and hence exist in any orbifold CFT. Additionally, we investigate non-universal defects arising from the topological defects of the seed CFT. We argue that there exist universal defects that are non-trivial in the large-N limit, making them relevant for the AdS3/CFT2 correspondence. We then focus on AdS3×S3 × M4 with one unit of NS-NS flux and propose an explicit realization of these defects on the worldsheet. © The Author(s) 2024.