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SUMMARY:Twisting Asymptotically-Flat Spacetimes
DTSTART:20260603T124500Z
DTEND:20260603T140000Z
DTSTAMP:20260615T182300Z
UID:indico-event-16680@indico.math.cnrs.fr
CONTACT:cecile@ihes.fr
DESCRIPTION:Speakers: Marc Geiller (ENS Lyon)\n\nSéminaire Amplitudes et 
 Gravitation sur l'Yvette (IHES/IPhT)\nI will present the detailed construc
 tion of an extension of the Bondi framework which includes a non-vanishing
  twist\, i.e. the relaxation of the hyperspace-orthogonality condition. Th
 is extension has several advantages which have been noted in recent work. 
 First\, it allows to access a Carroll-covariant structure on Scri. Second\
 , and most importantly\, the presence of a non-vanishing twist allows to w
 rite all the algebraically special solutions in finite form. This includes
  for example Kerr or supertranslated Schwarzschild\, which would otherwise
  require an infinite 1/r expansion when written in the standard non-twisti
 ng Bondi gauge. This opens the possibility of defining symplectic symmetri
 es for these algebraically special solutions. The construction of the alge
 braically general solutions near null infinity requires the use of a combi
 nation of the Newman-Penrose and metric formalisms\, which will be present
 ed in detail.\n \nPour être informé des prochains séminaires vous pouv
 ez vous abonner à la liste de diffusion en écrivant un mail à sympa@lis
 tes.math.cnrs.fr avec comme sujet: "subscribe seminaire_physique PRENOM NO
 M"(indiquez vos propres prénom et nom) et laissez le corps du message vid
 e.\n\nhttps://indico.math.cnrs.fr/event/16680/
LOCATION:Amphithéâtre Léon Motchane (IHES)
URL:https://indico.math.cnrs.fr/event/16680/
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