Speaker
Description
The AdS/CFT correspondence provides us with the best working example of the holographic principle. The holographic principle is used to study quantum gravity observables living on the conformal boundary of space-time. For example, this has been applied in the AdS/CFT correspondence, where we studied that quantum gravity observables on the boundary of (d+1)-dimensional AdS space are equivalent to correlation functions of a (non-gravitational) Conformal Field Theory (CFT) in d-dimensional Minkowski space. The natural question is to ask whether this understanding can be extended to space-times closer to that of our universe. One proposal for holography in flat space is celestial holography, where the boundary observables live on the celestial sphere at null infinity of Minkowski space. Recently it has been realized that celestial correlation functions can be written in the more familiar language of AdS/CFT by perturbatively expressing them in terms of Witten diagrams in Euclidean Anti-de Sitter space (EAdS). In this poster I will present that in perturbation theory such celestial correlation functions admit a conformal partial wave expansion with meromorphic spectral density, and hence also an expansion into conformal blocks.