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Gravitational waves in a de Sitter universe

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 نشر من قبل Nigel Bishop
 تاريخ النشر 2015
  مجال البحث فيزياء
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 تأليف Nigel T. Bishop




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The construction of exact linearized solutions to the Einstein equations within the Bondi-Sachs formalism is extended to the case of linearization about de Sitter spacetime. The gravitational wave field measured by distant observers is constructed, leading to a determination of the energy measured by such observers. It is found that gravitational wave energy conservation does not normally apply to inertial observers, but that it can be formulated for a class of accelerated observers, i.e. with worldlines that are timelike but not geodesic.



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