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arXiv · 1101.6007

QED coupled to QEG

Ulrich Harst·Martin Reuter
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Abstract

We discuss the non-perturbative renormalization group flow of Quantum Electrodynamics (QED) coupled to Quantum Einstein Gravity (QEG) and explore the possibilities for defining its continuum limit at a fixed point that would lead to a non-trivial, i.e. interacting field theory. We find two fixed points suitable for the Asymptotic Safety construction. In the first case, the fine-structure constant vanishes at the fixed point and its infrared ("renormalized") value is a free parameter not determined by the theory itself. In the second case, the fixed point value of the fine-structure constant is non-zero, and its infrared value is a computable prediction of the theory.

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Ulrich Harst, Martin Reuter. 2011-01-31. QED coupled to QEG. https://doi.org/10.1007/jhep05(2011)119

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