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arXiv · 1711.11372

Quantum Gates to other Universes

Constantin Bachas·Ioannis Lavdas
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Abstract

We present a microscopic model of a bridge connecting two large Anti-de-Sitter Universes. The Universes admit a holographic description as three-dimensional ${\cal N}=4$ supersymmetric gauge theories based on large linear quivers, and the bridge is a small rank-$n$ gauge group that acts as a messenger. On the gravity side, the bridge is a piece of a highly-curved AdS$_5\times$S$_5$ throat carrying $n$ units of five-form flux. We derive a universal expression for the mixing of the two massless gravitons: $M^2 \simeq 3n^2 (κ_4^2 + κ_4^{\prime\,2})/16π^2$, where $M$ is the mass splitting of the gravitons, $κ_4^2, κ_4^{\prime\,2}$ are the effective gravitational couplings of the AdS$_4$ Universes, and $n$ is the quantized charge of the gate. This agrees with earlier results based on double-trace deformations, with the important difference that the effective coupling is here quantized. We argue that the apparent non-localities of holographic double-trace models are resolved by integrating-in the (scarce) degrees of freedom of the gate.

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Constantin Bachas, Ioannis Lavdas. 2018-07-01. Quantum Gates to other Universes. https://doi.org/10.1002/prop.201700096

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