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arXiv · hep-ph/0404182

Scale of Quantum Gravity

Tao Han·Scott Willenbrock
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Abstract

In the effective field theory of quantum gravitation coupled to N_s scalars, N_f fermions, and N_V vectors, tree unitarity is violated at an energy squared of E_{CM}^2 = 20(G_N N)^{-1}, where N = {2/3}N_s + N_f + 4N_V and G_N is Newton's constant. This is related to radiative corrections proportional to G_N N E^2 (where E is the typical energy), due to loops of such particles. New physics must enter before E_{CM}=5.6 x 10^{18} GeV in the standard model, and 4.6 x 10^{18} GeV in the minimal supersymmetric standard model.

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Tao Han, Scott Willenbrock. 2005-04-27. Scale of Quantum Gravity. https://doi.org/10.1016/j.physletb.2005.04.040

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