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Beyond Adiabatic Elimination: Systematic Expansions

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 نشر من قبل Inigo L. Egusquiza
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف I. L. Egusquiza




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We restate the adiabatic elimination approximation as the first term in a singular perturbation expansion. We use the invariant manifold formalism for singular perturbations in dynamical systems to identify systematic improvements on adiabatic elimination, connecting with well established quantum mechanical perturbation methods. We prove convergence of the expansions when energy scales are well separated. We state and solve the problem of hermiticity of improved effective hamiltonians.



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