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UID:2503@qft.physik.hu-berlin.de
DTSTART;TZID=Europe/Berlin:20260213T110000
DTEND;TZID=Europe/Berlin:20260213T120000
DTSTAMP:20260205T121153Z
URL:https://qft.physik.hu-berlin.de/next-seminars/dogan-akpinar/
SUMMARY:Dogan Akpinar - 
DESCRIPTION:Title: Precision Kerr Black Hole Dynamics from Scattering Ampli
 tudes\n\nAbstract: Scattering amplitudes have emerged as a powerful tool f
 or computing classical observables in two-body gravitational dynamics. In 
 this talk\, I will present new progress in applying these methods to Kerr 
 black hole scattering. A central theme is the treatment of Kerr black hole
 s as point particles in fixed-spin representations\, which introduces a su
 btle mixing of quantum and classical data associated with the spin Casimir
  S^2. We resolve this ambiguity using our spin interpolation method. Build
 ing on this framework\, we compute the classical two-loop amplitude throug
 h quartic order in spin\, enabling the extraction of physical (non-aligned
  spin) observables such as the linear and angular impulses via covariant D
 irac brackets. Remarkably\, the resulting amplitude exhibits a spin-shift 
 symmetry: it remains invariant under shifts of the black hole spin by the 
 momentum transfer in the scattering process. Finally\, we combine the radi
 ation-reaction result proposed by Alessio and Di Vecchia with the Dirac br
 acket formalism to obtain radiation-reaction contributions to observables 
 at all orders in spin\, going beyond the aligned-spin limit. Our results a
 dvance the state of the art in the understanding of spinning binary dynami
 cs in general relativity and demonstrates the power and simplicity of the 
 Dirac bracket approach for relating scattering amplitudes to classical obs
 ervables.
CATEGORIES:ERC Group Seminar
LOCATION:Room 1.107\, IRIS Building\, Zum Großen Windkanal 2\, Berlin\, Ge
 rmany
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=Zum Großen Windkanal 2\, B
 erlin\, Germany;X-APPLE-RADIUS=100;X-TITLE=Room 1.107\, IRIS Building:geo:
 0,0
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DTSTART:20251026T020000
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