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arXiv · 2111.15529

Manifestly gauge invariant exact renormalization group for quantum electrodynamics

Yuki Miyakawa·Hidenori Sonoda·Hiroshi Suzuki
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Abstract

We formulate quantum electrodynamics on the basis of gauge (or BRST) covariant diffusion equations of fields. This is a particular example of the gradient flow exact renormalization group (GFERG). The resulting Wilson action fulfills a simple gauge Ward--Takahashi identity. We solve the GFERG equation around the Gaussian fixed point to the second order in gauge coupling and obtain the 1-loop beta function and anomalous dimensions. The anomalous dimension of the electron field coincides with that of the fermion field diffused by a gauge covariant flow equation of L\"uscher.

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Yuki Miyakawa, Hidenori Sonoda, Hiroshi Suzuki. 2021-11-30. Manifestly gauge invariant exact renormalization group for quantum electrodynamics. https://arxiv.org/abs/2111.15529

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