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arXiv · hep-th/0609199

On the Standard Approach to Renormalization Group Improvement

F. A. Chishtie·V. Elias·R. B. Mann·D. G. C. McKeon·T. G. Steele
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Abstract

Two approaches to renormalization-group improvement are examined: the substitution of the solutions of running couplings, masses and fields into perturbatively computed quantities is compared with the systematic sum of all the leading log (LL), next-to-leading log (NLL) etc. contributions to radiatively corrected processes, with n-loop expressions for the running quantities being responsible for summing N^{n}LL contributions. A detailed comparison of these procedures is made in the context of the effective potential V in the 4-dimensional O(4) massless $λϕ^{4}$ model, showing the distinction between these procedures at two-loop order when considering the NLL contributions to the effective potential V.

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F. A. Chishtie, V. Elias, R. B. Mann, D. G. C. McKeon, T. G. Steele. 2006-09-27. On the Standard Approach to Renormalization Group Improvement. https://doi.org/10.1142/s0218301307006095

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