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arXiv · hep-th/9507155

Convergent sequences of perturbative approximations for the anharmonic oscillator I. Harmonic approach

B. Bellet·P. Garcia·and A. Neveu
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Abstract

We present numerical evidence that a simple variational improvement of the ordinary perturbation theory of the quantum anharmonic oscillator can give a convergent sequence of approximations even in the extreme strong coupling limit, the purely anharmonic case. Some of the new techniques of this paper can be extended to renormalizable field theories.

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B. Bellet, P. Garcia, and A. Neveu. 1995-07-28. Convergent sequences of perturbative approximations for the anharmonic oscillator I. Harmonic approach. https://doi.org/10.1142/s0217751x9600256x

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