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arXiv · 0912.2726

Rigorous Limits on the Interaction Strength in Quantum Field Theory

Francesco Caracciolo·Slava Rychkov
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Abstract

We derive model-independent, universal upper bounds on the Operator Product Expansion (OPE) coefficients in unitary 4-dimensional Conformal Field Theories. The method uses the conformal block decomposition and the crossing symmetry constraint of the 4-point function. In particular, the OPE coefficient of three identical dimension $d$ scalar primaries is found to be bounded by ~ 10(d-1) for 1<d<1.7. This puts strong limits on unparticle self-interaction cross sections at the LHC.

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Francesco Caracciolo, Slava Rychkov. 2009-12-15. Rigorous Limits on the Interaction Strength in Quantum Field Theory. https://doi.org/10.1103/physrevd.81.085037

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