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arXiv · 1411.1923

Why should we care about the top quark Yukawa coupling?

Fedor Bezrukov·Mikhail Shaposhnikov
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Abstract

In the cosmological context, for the Standard Model to be valid up to the scale of inflation, the top quark Yukawa coupling $y_t$ should not exceed the critical value $y_t^{crit}$, coinciding with good precision (about 0.02%) with the requirement of the stability of the electroweak vacuum. So, the exact measurements of $y_t$ may give an insight on the possible existence and the energy scale of new physics above 100 GeV, which is extremely sensitive to $y_t$. We overview the most recent theoretical computations of $y_t^{crit}$ and the experimental measurements of $y_t$. Within the theoretical and experimental uncertainties in $y_t$ the required scale of new physics varies from $10^7$ GeV to the Planck scale, urging for precise determination of the top quark Yukawa coupling.

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Fedor Bezrukov, Mikhail Shaposhnikov. 2015-03-12. Why should we care about the top quark Yukawa coupling?. https://doi.org/10.1134/s1063776115030152

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