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arXiv · 1912.01766

Stochastic Renormalization Group and Gradient Flow in Scalar Field Theory

Andrea Carosso·Anna Hasenfratz·Ethan T. Neil
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Abstract

Recently, the connections between gradient flow and renormalization group have been explored analytically and numerically. Gradient flow (when modified by a field rescaling) can be characterized as a continuous blocking transformation. In this work, we draw a connection between gradient flow and functional renormalization group by describing how FRG can be represented by a stochastic process, and how the stochastic observables relate to gradient flow observables. The relation implies correlator scaling formulae that can be applied numerically in lattice simulations. We present preliminary results on anomalous dimensions obtained from such measurements in the context of 3-dimensional lattice $\phi^4$ theory.

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Andrea Carosso, Anna Hasenfratz, Ethan T. Neil. 2019-12-04. Stochastic Renormalization Group and Gradient Flow in Scalar Field Theory. https://arxiv.org/abs/1912.01766

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