Quantum gravitational contributions to the beta function of quantum   electrodynamics
  We show in a diagrammatic and regularization independent analysis that the quadratic contribu- tion to the beta function which has been conjectured to render quantum electrodynamics asymp- totically free near the Planck scale has its origin in a surface term. Such surface term is intrinsically arbitrarily valued and it is argued to vanish in a consistent treatment of the model. 
J. C. C. Felipe, L. C. T. Brito, Marcos Sampaio and M. C. Nemes
hep-th