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Gross-Pitaevskii Dynamics for Bose-Einstein Condensates

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 نشر من قبل Christian Brennecke
 تاريخ النشر 2017
  مجال البحث فيزياء
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We study the time-evolution of initially trapped Bose-Einstein condensates in the Gross-Pitaevskii regime. Under a physically motivated assumption on the energy of the initial data, we show that condensation is preserved by the many-body evolution and that the dynamics of the condensate wave function can be described by the time-dependent Gross-Pitaevskii equation. With respect to previous works, we provide optimal bounds on the rate of condensation (i.e. on the number of excitations of the Bose-Einstein condensate). To reach this goal, we combine the method of cite{LNS}, where fluctuations around the Hartree dynamics for $N$-particle initial data in the mean-field regime have been analyzed, with ideas from cite{BDS}, where the evolution of Fock-space initial data in the Gross-Pitaevskii regime has been considered.

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