On the Role of the Higgs Mechanism in Present Electroweak Precision Tests

Abstract

Based on the observables $\text{MW}$, ${\Gamma }_l$, ${\overline{\text{sw}}}^2({\text{MZ}}^2)$, we evaluate the parameters $\Delta x,\Delta y$ and $\epsilon$ at one-loop level within an electroweak massive vector-boson theory, which does not employ the Higgs mechanism. The theoretical results are consistent with the experimental ones on $\Delta x$, $\Delta y$, $\epsilon$. The theoretical prediction for $\Delta y$ coincides with the standard-model one (apart from numerically irrelevant terms which vanish for $\text{MH}\to \infty$). Non-renormalizability only affects $\Delta x$ and $\epsilon$, which differ from the standard-model results by the replacement $\log \text{MH}\to \log \Lambda$ for a heavy Higgs mass, $\text{MH}$ (where $\Lambda$ denotes an effective UV cut-off).

Comments: 10 pages latex, BI-TP 94/31