Скачать или смотреть A physical protocol for boundary observations in quantum gravity - Chandramouli Chowdhury

ICTS string virtual seminar series
25th September, 2020

A physical protocol for observers near the boundary to obtain bulk information in quantum gravity

Chandramouli Chowdhury
International Centre for Theoretical Sciences, Bengaluru

Abstract: "We consider a set of observers who live near the boundary of global AdS, and are allowed to act only with simple low-energy unitaries and make measurements in a small interval of time. The observers are not allowed to leave the near-boundary region. We describe a physical protocol that nevertheless allows these observers to obtain detailed information about the bulk state. This protocol utilizes the leading gravitational back-reaction of a bulk excitation on the metric, and also relies on the entanglement-structure of the vacuum. For low-energy states, we show how the near-boundary observers can use this protocol to completely identify the bulk state. We explain why the protocol fails completely in theories without gravity, including non-gravitational gauge theories. This provides perturbative evidence for the claim that one of the signatures of holography -- the fact that information about the bulk is also available near the boundary -- is already visible in semiclassical gravity.

This is work done in collaboration with Olga Papadoulaki and Suvrat Raju and the reference is: https://arxiv.org/abs/2008.01740."