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arXiv · 1708.01328

Boundary Holographic Witten Diagrams

Andreas Karch·Yoshiki Sato
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Abstract

In this paper we discuss geodesic Witten diagrams in generic holographic conformal field theories with boundary or defect. Boundary CFTs allow two different decompositions of two-point functions into conformal blocks: boundary channel and ambient channel. Building on earlier work, we derive a holographic dual of the boundary channel decomposition in terms of bulk-to-bulk propagators on lower dimensional AdS slices. In the situation in which we can treat the boundary or defect as a perturbation around pure AdS spacetime, we obtain the leading corrections to the two-point function both in boundary and ambient channel in terms of geodesic Witten diagrams which exactly reproduce the decomposition into corresponding conformal blocks on the field theory side.

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Andreas Karch, Yoshiki Sato. 2017-10-03. Boundary Holographic Witten Diagrams. https://doi.org/10.1007/jhep09(2017)121

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