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arXiv · 2003.05501

Holographic duality and mode stability of de Sitter space in semiclassical gravity

Paul M. Chesler·Abraham Loeb
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Abstract

We employ holographic duality to compute $\langle T_{\mu \nu} \rangle$ in strongly coupled $\mathcal N = 4$ supersymmetric Yang-Mills theory and then study evolution of the semiclassical Einstein field equations sourced by $\langle T_{\mu \nu} \rangle$. Linearizing about de Sitter space, we find that the semiclassical equations of motion reduce to a four dimensional scalar wave equation coupled to a five dimensional scalar wave equation. We compute the mode spectrum of these equations and find that there exists a critical value of the Hubble constant $H_c$ for which de Sitter space is unstable when $H < H_c$ and mode stable when $H > H_c$.

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Paul M. Chesler, Abraham Loeb. 2020-03-11. Holographic duality and mode stability of de Sitter space in semiclassical gravity. https://doi.org/10.1088/1475-7516/2020/11/010

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