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arXiv · 1009.6048

Exact renormalization group and Phi-derivable approximations

Jean-Paul Blaizot·Jan M. Pawlowski·Urko Reinosa
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Abstract

We show that the so-called Phi-derivable approximations can be combined with the exact renormalization group to provide efficient non-perturbative approximation schemes. On the one hand, the Phi-derivable approximations allow for a simple truncation of the infinite hierarchy of the renormalization group flow equations. On the other hand, the flow equations turn the non linear equations that derive from the Phi-derivable approximations into an initial value problem, offering new practical ways to solve these equations.

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Jean-Paul Blaizot, Jan M. Pawlowski, Urko Reinosa. 2010-09-30. Exact renormalization group and Phi-derivable approximations. https://doi.org/10.1016/j.physletb.2010.12.058

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