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arXiv · 1606.06951

The effective exponent gamma(Q) and the slope of the beta function

P. M. Stevenson
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Abstract

The slope of the beta function at a fixed point is commonly thought to be RG invariant and to be the critical exponent gamma* that governs the approach of any physical quantity R to its fixed-point limit: R*-R proportional to Q^gamma*. Chyla has shown that this is not quite true. Here we define a proper RG invariant, the "effective exponent" gamma(Q), whose fixed-point limit is the true gamma*.

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P. M. Stevenson. 2016-09-01. The effective exponent gamma(Q) and the slope of the beta function. https://doi.org/10.1016/j.physletb.2016.08.061

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