Variational Resummation of Divergent Series with Known Large-order Behavior Typeset Using Revt E X
نویسنده
چکیده
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 coeecients. We correct this deeciency and present a method of resumming divergent series with their proper large-order behavior. For a given set of expansion coeecients, knowledge of the large-order behavior considerably improves the quality of the approximation.
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