BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Monica Pate (Harvard) DTSTART:20210324T150000Z DTEND:20210324T160000Z DTSTAMP:20260423T024622Z UID:SISSAHEP/6 DESCRIPTION:Title: Scattering Amplitudes on the Celestial sphere\nby Monica Pate (Harvar d) as part of SISSA HEP seminars\n\n\nAbstract\nThe identification of quan tum field theoretic soft theorems with constraints from infinite-dimension al asymptotic symmetries offers exciting prospects for solving the scatter ing problem in quantum gravity. In four spacetime dimensions\, the asymp totic symmetry group includes the local conformal (Virasoro) symmetry of t wo dimensions\, motivating the proposal that 4D scattering is holographi cally dual to a 2D conformal theory. Lorentz symmetry in four dimensions comprises the global part of the 2D conformal group of the dual. Asympto tic particles in boost as opposed to standard momentum eigenstates transf orm like primary operators\, and thereby manifestly exhibit the underlying conformal symmetry. Scattering amplitudes for such states -- known as c elestial amplitudes -- involve contributions from asymptotic particles of arbitrarily high energy and accordingly do not respect the familiar paradi gm of Wilsonian IR/UV decoupling. Nevertheless\, I will describe how vario us observable IR and UV phenomena can be canonically extracted directly fr om celestial amplitudes. Moreover\, a manifestly Lorentz covariant formul ation of scattering constraints is necessary for their direct application to celestial amplitudes. I will explain how constraints from Poincare sym metry\, soft UV behavior of quantum gravity\, and asymptotic symmetries ar e covariantly implemented in celestial amplitudes.\n LOCATION:https://researchseminars.org/talk/SISSAHEP/6/ END:VEVENT END:VCALENDAR