Entanglement and Chaos in De Sitter Space Holography: An SYK Example

Document Type : Regular article


Stanford Institute for Theoretical Physics and Department of Physics


Entanglement, chaos, and complexity are as important for de Sitter space as for AdS, and for black holes. There are similarities and also great differences between AdS and dS in how these concepts are manifested in the space-time geometry.
In the first part of this paper the Ryu–Takayanagi prescription, the theory of fast-scrambling, and the holographic complexity correspondence are reformulated for de Sitter space. Criteria are proposed for a holographic model to describe de Sitter space. The criteria can be summarized by the requirement that scrambling and complexity growth must be ``hyperfast."
In the later part of the paper I show that a certain limit of the SYK model satisfies the hyperfast criterion. This leads to
the radical conjecture that a limit of SYK is indeed a concrete, computable, holographic model of de Sitter space. Calculations are described which support the conjecture.



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Volume 1, Issue 1
November 2021
Pages 1-22
  • Receive Date: 28 September 2021
  • Revise Date: 11 October 2021
  • Accept Date: 29 October 2021