QED coupled to QEG

  • U. HarstEmail author
  • M. Reuter


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 α 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 α is non-zero, and its infrared value is a computable prediction of the theory.


Models of Quantum Gravity Renormalization Group Asymptotic Freedom 


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Copyright information

© SISSA, Trieste, Italy 2011

Authors and Affiliations

  1. 1.Institute of PhysicsUniversity of MainzMainzGermany

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