Consider the Schro¨dinger equation Ày 00 þ V ðxÞy ¼ ly with a periodic real-valued L 2 -potential V of period 1; VðxÞ ¼ P 1 m¼À1 vðmÞ expð2pimxÞ: Let fl À n ; l þ n g be its zones of instability, i.e. fl À n ; l þ n g are pairs of periodic and antiperiodic eigenvalues, and b 2 ð0; 1Þ determines Gevr
The Gevrey Asymptotics in the Case of Singular Perturbations
✍ Scribed by Yasutaka Sibuya
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 327 KB
- Volume
- 165
- Category
- Article
- ISSN
- 0022-0396
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✦ Synopsis
In this paper, we present results in the Gevrey asymptotics which correspond to some existing results concerning asymptotic solutions in the Poincare asymptotics of singularly perturbed ordinary differential equations. The main idea is based on a characterization of the Gevrey flat functions and a characterizaton of the Gevrey asymptotic expansions as it had been already exhibited by Y.
📜 SIMILAR VOLUMES
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For a class of compactly supported hypoelliptic perturbations of the Laplacian in R n , n 3 odd, we prove that an asymptotic on the number of the eigenvalues of the corresponding reference operator implies a similar asymptotic for the number of the scattering poles.
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