Geometry And Quantum Noise

TL;DR

This paper analyzes the quantum noise in AdS/CFT correlation functions, linking the noise's fine structure to bulk geometry and chaos, revealing suppression by chaos and impurity, and comparing EPR correlations across states.

Contribution

It provides a detailed estimate of quantum noise oscillations in AdS/CFT, connecting them to geometric features and chaos, and compares EPR correlation noise in different entangled states.

Findings

Quantum noise oscillations are linked to bulk geometry.

Chaos suppresses the noise level significantly.

EPR correlation noise is consistent across different entangled states.

Abstract

We study the fine structure of long-time quantum noise in correlation functions of AdS/CFT systems. Under standard assumptions of quantum chaos for the dynamics and the observables, we estimate the size of exponentially small oscillations and trace them back to geometrical features of the bulk system. The noise level is highly suppressed by the amount of dynamical chaos and the amount of quantum impurity in the states. This implies that, despite their missing on the details of Poincare recurrences, `virtual' thermal AdS phases do control the overall noise amplitude even at high temperatures where the thermal ensemble is dominated by large AdS black holes. We also study EPR correlations and find that, in contrast to the behavior of large correlation peaks, their noise level is the same in TFD states and in more general highly entangled states.