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Particle-Number Projection and the Density Functional Theory

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 نشر من قبل Jacek Dobaczewski
 تاريخ النشر 2007
  مجال البحث
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In the framework of the Density Functional Theory for superconductors, we study the restoration of the particle number symmetry by means of the projection technique. Conceptual problems are outlined and numerical difficulties are discussed. Both are related to the fact that neither the many-body Hamiltonian nor the wave function of the system appear explicitly in the Density Functional Theory. Similar obstacles are encountered in self-consistent theories utilizing density-dependent effective interactions.



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