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arXiv · hep-th/9912141

Flow Equations for U_k and Z_k

Vincenzo Branchina
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Abstract

By considering the gradient expansion for the wilsonian effective action S_k of a single component scalar field theory truncated to the first two terms, the potential U_k and the kinetic term Z_k, I show that the recent claim that different expansion of the fluctuation determinant give rise to different renormalization group equations for Z_k is incorrect. The correct procedure to derive this equation is presented and the set of coupled differential equations for U_k and Z_k is definitely established.

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Vincenzo Branchina. 1999-12-16. Flow Equations for U_k and Z_k. https://doi.org/10.1103/physrevd.62.065010

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