English

Variational Resummation of Divergent Series with known Large-Order Behavior

Quantum Physics 2009-10-28 v1

Abstract

Recently-developed variational perturbation expansions converge exponentially fast for positive coupling constants. They do not, however, possess the correct left-hand cut in the complex coupling constant plane, implying a wrong large-order behavior of their Taylor expansion coefficients. We correct this deficiency and present a method of resumming divergent series with their proper large-order behavior. For a given set of expansion coefficients, knowledge of the large-order behavior considerably improves the quality of the approximation.

Keywords

Cite

@article{arxiv.quant-ph/9507009,
  title  = {Variational Resummation of Divergent Series with known Large-Order Behavior},
  author = {H. Kleinert},
  journal= {arXiv preprint arXiv:quant-ph/9507009},
  year   = {2009}
}

Comments

Postscript, see also http://www.physik.fu-berlin.de/~kleinert/institution.html