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Constraints on extra-dimensional theories from virtual-graviton exchange

Gian Francesco Giudice·Alessandro Strumia
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Abstract

We study the effective interactions induced by loops of extra-dimensional gravitons and show the special role of a specific dimension-6 four-fermion operator, product of two flavour-universal axial currents. By introducing an ultraviolet cut-off, we compare the present constraints on low-scale quantum gravity from various processes involving real-graviton emission and virtual-graviton exchange. The LEP2 limits on dimension-6 four-fermion interactions give one of the strongest constraint on the theory, in particular excluding the case of strongly-interacting gravity at the weak scale.

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Gian Francesco Giudice, Alessandro Strumia. 2003-01-27. Constraints on extra-dimensional theories from virtual-graviton exchange. https://doi.org/10.1016/s0550-3213(03)00404-8

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