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Special Condensed Atomic Molecular Physics (CAMP) Seminar - Xiaoliang Qi, Stanford

Special Condensed Atomic Molecular Physics (CAMP) Seminar - Xiaoliang Qi, Stanford

339 Davey Lab

2023-03-27

Title: Spacetime Mutual Information

Abstract: Most quantum information measures are defined for quantum states. For example, mutual information measures the correlation between two subsystems in a quantum state. It is natural to ask whether correlation in spacetime can be characterized by some generalization of mutual information. In this work, we propose a space-time generalization of mutual information. The key idea is to consider a general “quantum experiment” that measures the correlation between two space-time regions, and use the setup of hypothesis testing. We discuss various properties of the spacetime mutual information, including how it provides an upper bound for all connected correlation functions, which is a direct generalization of the similar property of ordinary mutual information.

TimeSpeakerTitle
10:00Xiaoliang QiSpacetime Mutual Information
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Monica The IGC wordmark was created by Monica Rincon Ramirez, while she was a graduate student at the Institute for Gravitation and the Cosmos (IGC). Monica enjoys drawing new connections between fundamental theory and observations. Her graduate work includes specialized topics in general relativity, loop quantum gravity, and quantum fields in cosmological backgrounds. In particular, her thesis work focused on finding effective quantum corrections to gravitational phenomena from spinfoams, and applications to cosmology. She received her PhD in 2024.

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