Events Daily

Friday, October 13, 2023

Postdoc HepTh Discussion Group
Event Type: ArXiv Discussion
Time: 12:00 PM - 1:30 PM
Location: 726 Broadway, 902, Lg Conf

From shockwaves to gravitational memory: new approaches in flat space holography
Kathryn Zurek, Caltech
Event Type: HEP Seminar
Time: 3:00 PM - 4:15 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: We discuss how shockwave geometries, studied since ’t Hooft and Dray, give access to aspects of flat space holography. We first show how the ’t Hooft commutation relations of shockwave operators are equivalent to the commutation relation between soft and Goldstone modes familiar from celestial holography. We demonstrate this equivalence via a diffeomorphism that takes the shockwave metric to a memory metric. Next we show that the shockwave effective action is equivalent to an object very similar to the modular Hamiltonian. We compute the fluctuations in the modular Hamiltonian implied by the ’t Hooft commutation relations, and show they obey an area law. Finally, we discuss metric fluctuations from shockwaves produced by vacuum energy fluctuations.