Universality in the exact renormalization group: comparison to perturbation theory

Jose Gaite

doi:10.3390/universe9090409

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arXiv · 2304.00597

Universality in the exact renormalization group: comparison to perturbation theory

Jose Gaite

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Abstract

Various formulations of the exact renormalization group can be compared in the perturbative domain, in which we have reliable expressions for regularization-independent (universal) quantities. We consider the renormalization of the $\lambda\phi^4$ theory in three dimensions and make a comparison between the sharp-cutoff regularization method and other more recent methods. They all give good results, which only differ by small non-universal terms.

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Jose Gaite. 2023-04-02. Universality in the exact renormalization group: comparison to perturbation theory. https://doi.org/10.3390/universe9090409

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