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arXiv · 1710.10409

On the geometry of the theory space in the ERG formalism

C. Pagani·H. Sonoda
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Abstract

We consider the theory space as a manifold whose coordinates are given by the couplings appearing in the Wilson action. We discuss how to introduce connections on this theory space. A particularly intriguing connection can be defined directly from the solution of the exact renormalization group (ERG) equation. We advocate a geometric viewpoint that lets us define straightforwardly physically relevant quantities invariant under the changes of a renormalization scheme.

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C. Pagani, H. Sonoda. 2017-10-28. On the geometry of the theory space in the ERG formalism. https://doi.org/10.1103/physrevd.97.025015

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