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arXiv · 0812.3262

Flavor Changing Fermion-Graviton Vertices

G. Degrassi·E. Gabrielli·L. Trentadue
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Abstract

We study the flavor-changing quark-graviton vertex that is induced at the one-loop level when gravitational interactions are coupled to the standard model. Because of the conservation of the energy-momentum tensor the corresponding form factors turn out to be finite and gauge-invariant. Analytical expressions of the form factors are provided at leading order in the external masses. We show that flavor-changing interactions in gravity are local if the graviton is strictly massless while if the graviton has a small mass long-range interactions inducing a flavor-changing contribution in the Newton potential appear. Flavor-changing processes with massive spin-2 particles are also briefly discussed. These results can be generalized to the case of the lepton-graviton coupling.

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G. Degrassi, E. Gabrielli, L. Trentadue. 2009-03-11. Flavor Changing Fermion-Graviton Vertices. https://doi.org/10.1103/physrevd.79.053004

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