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arXiv · 1705.05362

The Mellin Formalism for Boundary CFT$_d$

Leonardo Rastelli·Xinan Zhou
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Abstract

We extend the Mellin representation of conformal field theory (CFT) to allow for conformal boundaries and interfaces. We consider the simplest holographic setup dual to an interface CFT - a brane filling an $AdS_{d}$ subspace of $AdS_{d+1}$ - and perform a systematic study of Witten diagrams in this setup. As a byproduct of our analysis, we show that geodesic Witten diagrams in this geometry reproduce interface CFT$_d$ conformal blocks, generalizing the analogous statement for CFTs with no defects.

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Leonardo Rastelli, Xinan Zhou. 2017-10-27. The Mellin Formalism for Boundary CFT$_d$. https://doi.org/10.1007/jhep10(2017)146

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