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Existence and Uniqueness of Exact WKB Solutions for Second-Order Singularly Perturbed Linear ODEs

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 نشر من قبل Nikita Nikolaev
 تاريخ النشر 2021
  مجال البحث فيزياء
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 تأليف Nikita Nikolaev




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We prove an existence and uniqueness theorem for exact WKB solutions of general singularly perturbed linear second-order ODEs in the complex domain. These include the one-dimensional time-independent complex Schrodinger equation. Notably, our results are valid both in the case of generic WKB trajectories as well as closed WKB trajectories. We also explain in what sense exact and formal WKB solutions form a basis. As a corollary of the proof, we establish the Borel summability of formal WKB solutions for a large class of problems, and derive an explicit formula for the Borel transform.

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