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Resummation of Nonalternating Divergent Perturbative Expansions
Published
Author(s)
U Jentschura
Abstract
A procedure for the resummation of nonalternating divergent perturbation series is described. The prescription combines the Borel transformation with Pade approximations and a special integration contour for the evaluation of a generalized Borel integral. Nonperturbative imaginary contributions can be inferred form the purely real perturbative coefficients. A connection is drawn from the quantum field theoretic problem of ressummation to divergent perturbative expansions in other areas of physics.
Citation
Physical Review D (Particles, Fields, Gravitation and Cosmology)
Volume
62
Issue
No. 7
Pub Type
Journals
Keywords
asymptotic properties, autoionization, line widths, nonperturbative techniques, perturbation theory, QED, Zeeman and Stark effects
Citation
Jentschura, U.
(2000),
Resummation of Nonalternating Divergent Perturbative Expansions, Physical Review D (Particles, Fields, Gravitation and Cosmology)
(Accessed October 22, 2025)