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arXiv · 2108.10345

Looking for (and not finding) a bulk brane

Wyatt Reeves·Moshe Rozali·Petar Simidzija·James Sully·Christopher Waddell·David Wakeham
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Abstract

When does a holographic CFT with a boundary added to it (a BCFT) also have a `good' holographic dual with a localized gravitating end-of-the-world brane? We argue that the answer to this question is almost never. By studying Lorentzian BCFT correlators, we characterize constraints imposed on a BCFT by the existence of a bulk causal structure. We argue that approximate `bulk brane' singularities place restrictive constraints on the spectrum of a BCFT that are not expected to be true generically. We discuss how similar constraints implied by bulk causality might apply in higher-dimensional holographic descriptions of BCFTs involving a degenerating internal space. We suggest (although do not prove) that even these higher-dimensional holographic duals are not generic.

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Wyatt Reeves, Moshe Rozali, Petar Simidzija, James Sully, Christopher Waddell, David Wakeham. 2021-08-23. Looking for (and not finding) a bulk brane. https://doi.org/10.1007/jhep12(2021)002

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