Event

In this talk, I will discuss the implications of non-invertible topological defects on the worldsheet. I will consider two different setups where such defects arise in string theory. The first setup is toroidal compactification of string theory. In this case, I will show that we can construct a O(d,d,Q) groupoid of topological defects. These defects lead to global symmetries in low-energy supergravity. However, their Ward identities are violated by higher-order corrections in the string coupling. The second setup is string theory on AdS3 background with one unit of NS flux. In this case, the worldsheet theory is dual to the symmetric orbifold CFT at the boundary of AdS3. The latter has a large number of defects, and I will argue that they correspond to topological defects on the worldsheet.