# Baby Universes, Holography, and the Swampland

@article{McNamara2020BabyUH, title={Baby Universes, Holography, and the Swampland}, author={Jacob McNamara and Cumrun Vafa}, journal={arXiv: High Energy Physics - Theory}, year={2020} }

On the basis of a number of Swampland conditions, we argue that the Hilbert space of baby universe states must be one-dimensional in a consistent theory of quantum gravity. This scenario may be interpreted as a type of "Gauss's law for entropy" in quantum gravity, and provides a clean synthesis of the tension between Euclidean wormholes and a standard interpretation of the holographic dictionary, with no need for an ensemble. Our perspective relies crucially on the recently-proposed potential…

## 44 Citations

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Abstract
We study $$ \hat{\mathrm{CGHS}} $$
CGHS
̂
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