/
lectern.tv
Play15s30s1x0:00/--:--
DoneWatched
Expand
lectern.tv
0:20/1:06:39
3:18
1:48
2:48
1:53
1:13
1:41
4:24
1:00
1:02
0:38
3:26
6:34
0:49
1:46
1:15
3:10
3:25
2:24
2:49
4:22
6:20
3:40
0:58
4:21
1:20
Asymptotic Symmetries and Detectors: Part 1
Discover how gravitational memory, soft theorems, and celestial holography link universal asymptotic symmetries to physical detector measurements.
Explores the connection between asymptotic symmetries, soft theorems, and physical observables, focusing on memory effects and detectors in asymptotically flat spacetimes. Sabrina Pasterski derives memory observables and waveforms using Einstein's equations and Bondi gauge fall-offs, linking them to soft charges and celestial holography. The lecture concludes by discussing how S-matrix Ward identities can be translated into in-in correlators and energy-momentum tensor insertions.
Lecture Guide
- 1Asymptotic symmetries in asymptotically flat spacetimes lead to universal soft theorems and observable memory effects.
- 2Einstein's constraint equations in Bondi gauge relate the u-derivative of the Bondi mass to the shear and matter contributions.
- 3Geodesic deviation equations show that gravitational memory is directly proportional to asymptotic shear and wave form displacement.
- 4Soft charges and hard charges can be paired via antipodal matching conditions between future and past null infinity.
Proofs, Examples & Demos