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On the minimization of quantum entropies under local constraints

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 نشر من قبل Romain Duboscq
 تاريخ النشر 2017
  مجال البحث فيزياء
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 تأليف Romain Duboscq




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This work is concerned with the minimization of quantum entropies under local constraints of density, current, and energy. The problem arises in the work of Degond and Ringhofer about the derivation of quantum hydrodynamical models from first principles, and is an adaptation to the quantum setting of the moment closure strategy by entropy minimization encountered in kinetic equations. The main mathematical difficulty is the lack of compactness needed to recover the energy constraint. We circumvent this issue by a monotonicity argument involving energy, temperature and entropy, that is inspired by some thermodynamical considerations.



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