• Corpus ID: 215769038

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… 
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