Non--decoupling, triviality and the $ρ$ parameter

Kenichiro Aoki; Santiago Peris

doi:10.1007/bf01413109

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arXiv · hep-ph/9207203

Non--decoupling, triviality and the $ρ$ parameter

Kenichiro Aoki·Santiago Peris

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Abstract

The dependence of the $ρ$ parameter on the mass of the Higgs scalar and the top quark is computed non--perturbatively using the $1/N_F$ expansion in the standard model. We find an explicit expression for the $ρ$ parameter that requires the presence of a physical cutoff. This should come as no surprise since the theory is presumably trivial. By taking this cutoff into account, we find that the $ρ$ parameter can take values only within a limited range and has finite ambiguities that are suppressed by inverse powers of the cutoff scale, the so called ``scaling--violations". We find that large deviations from the perturbative results are possible, but only when the cutoff effects are also large.

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Kenichiro Aoki, Santiago Peris. 1992-11-04. Non--decoupling, triviality and the $ρ$ parameter. https://doi.org/10.1007/bf01413109

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