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The Standard Model hierarchy, fine-tuning, and negativity of the Higgs mass squared

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 نشر من قبل Marko B. Popovic
 تاريخ النشر 2002
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 تأليف Marko B. Popovic




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I discuss standard motivation for the new physics at the 1 TeV scale. Although the arguments for new exotic phenomena seem to be very supportive I argue that the Standard Model still might offer a good description far beyond this energy scale. I analyze three Standard Model cases with specific boundary conditions at the lowest energies. These conditions essentially eliminate the hierarchy and fine-tuning problems. In the first model where quartic scalar interactions are required to decouple, the Higgs is predicted to weigh around 39 GeV. In the second model with composite Higgs, the top Yukawa coupling is required to be one (by hand, i.e. reflecting the assumed ground state) and the Higgs mass of about 138 GeV is favored. The third model has condensation mechanism embedded in two dimensions. The top Yukawa coupling being one comes about as prediction rather then requirement, i.e. $g_t={3g_2 over 2}sqrt{1+{1over3}(g_1over g_2)^2} (1-textit{few}%)approx 1.025 (1-textit{few}%)$ where $g_2$, $g_1$ are electroweak $SU(2)times U(1)$ gauge couplings, and the SM Higgs is expected to weigh in between 114.8 and 118.6 GeV.

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