Speaker
Description
In this talk, I will consider "bottom-up" (toy) models of Einstein gravity with either gravitating domain walls or end-of-the-world (ETW) branes. In AdS/CFT language, these bulk objects are holographically dual to codimension-one conformal defects and boundaries, respectively. Depending on which type of model, one can study notions of either an AdS/DCFT or an AdS/BCFT correspondence. From here, in lieu of strictly working with "top-down constructions", i.e., proper 10- or 11-dimensional supersymmetric string theories with known holographic duals, one may wish to utilize the simpler bottom-up models (when possible) when exploring various aspects of holography. My goal in this talk is to address this desire indirectly by exploring the viability of the bottom-up models, which I will primarily do by comparing the bottom-up models' precision with results obtained from known top-down constructions. The physical quantities we compare are the holographic defect/boundary entanglement entropies (presumed to exist for the bottom-up models), which are interpreted through a shared quantity known as "\phi_{b}" which itself has both a bulk and boundary interpretation. In the bulk, \phi_{b} is the proper time of a geodesic null trajectory in the bulk from the conformal boundary to the domain-wall/ETW brane and back. In a dual boundary theory, \phi_{b} marks an (unexpected) seemingly apparent singularity in boundary correlators. The results of this analysis will be organized according to type of holographic dual, i.e. defect theories and boundary theories, respectively.
