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arXiv · hep-th/0109185

Once again: Instanton method vs. WKB

H. J. W. Müller-Kirsten·Jian-zu Zhang·Yunbo Zhang
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Abstract

A recent analytic test of the instanton method performed by comparing the exact spectrum of the Lam${\acute e}$ potential (derived from representations of a finite dimensional matrix expressed in terms of $su(2)$ generators) with the results of the tight--binding and instanton approximations as well as the standard WKB approximation is commented upon. It is pointed out that in the case of the Lam${\acute e}$ potential as well as others the WKB--related method of matched asymptotic expansions yields the exact instanton result as a result of boundary conditions imposed on wave functions which are matched in domains of overlap.

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H. J. W. Müller-Kirsten, Jian-zu Zhang, Yunbo Zhang. 2001-11-20. Once again: Instanton method vs. WKB. https://doi.org/10.1088/1126-6708%2F2001%2F11%2F011

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