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arXiv · 0912.0084

Efficient Evaluation of Effective Action in Radial Backgrounds

Hyunsoo Min
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Abstract

Recently a new caculational scheme for effective actions in radial background fields was developed. The effective action is expressed as an infinite sum of partial-wave contributions, using the rotational symmetry of the system. The sum becomes convergent after proper regularization and renormalization, but the rate of convergence is rather slow. We introduce a systematic way of accelerating the rate of convergence. This method is based on a radial WKB series in the angular momentum cut-off. We demonstrate the power of this scheme by applying it to the calculation of instanton determinant in QCD.

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Hyunsoo Min. 2009-12-01. Efficient Evaluation of Effective Action in Radial Backgrounds. https://doi.org/10.1142/9789814289931_0053

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