BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//CERN//INDICO//EN
BEGIN:VEVENT
SUMMARY:SUPERTRANSLATIONS\, ANGULAR MOMENTUM\, AND COVARIANCE IN 4D ASYMPT
 OTICALLY FLAT SPACE
DTSTART:20260506T123000Z
DTEND:20260506T133000Z
DTSTAMP:20260512T055500Z
UID:indico-event-1809@indico.dfa.unipd.it
DESCRIPTION:Speakers: Massimo Porrati\n\nThis talk reviews some aspects of
  the "angular momentum problem" in general relativity as well as of old an
 d new results in the search for covariant and supertranslation-invariant f
 ormulas for the flux of angular momentum and other Lorentz charges in asym
 ptotically flat spacetimes. It addresses in particular three problems with
  all existing solutions: 1) Supertranslation-invariance and covariance imp
 ly invariance under spacetime translations\; 2) the flux depends on redund
 ant auxiliary degrees of freedom that cannot be set to zero in all Lorentz
  frames without breaking Lorentz covariance\; 3) supertranslation-invarian
 t Lorentz charges do not generate the transformations of the Bondi mass as
 pect implied by the isometries of the asymptotic metric. The resolution of
  these problems leads to new\, covariant formulas for the fluxes that make
  explicit the choice of reference frame underpinning seemingly unambiguous
  results presented in the current literature. This choice will be describe
 d in some detail and an elementary method for measuring the rotational par
 t of the angular momentum aspect will be presented.\n\nhttps://indico.dfa.
 unipd.it/event/1809/
LOCATION:1/1-2 - Aula "C. Voci" (Dipartimento di Fisica e Astronomia - Edi
 ficio Marzolo)
URL:https://indico.dfa.unipd.it/event/1809/
END:VEVENT
END:VCALENDAR