Theory Seminar (High Energy/Cosmology) |
Events During the Week of January 24th through January 31st, 2021
Monday, January 25th, 2021
- No events scheduled
Tuesday, January 26th, 2021
- No events scheduled
Wednesday, January 27th, 2021
- No events scheduled
Thursday, January 28th, 2021
- No events scheduled
Friday, January 29th, 2021
- A physical protocol to obtain information in quantum gravity
- Time: 2:00 pm - 3:00 pm
- Place: For zoom link, sign up at:
- Speaker: Chandramouli Chowdhury, ICTS, Bangalore
- 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, in 2008.01740.
- Host: Lars Aalsma