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arXiv · 0811.2089

Remarkable coincidence for the top Yukawa coupling and an approximately massless bound state

C. D. Froggatt·H. B. Nielsen
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Abstract

We calculate, with several corrections, the non-relativistic binding by Higgs exchange and gluon exchange between six top and six anti-top quarks (actually replaced by left-handed b quarks from time to time). The remarkable result is that, within our calculational accuracy of the order of 14% in the top quark Yukawa coupling g_t, the experimental running top-quark Yukawa coupling g_t = 0.935 happens to have just that value which gives a perfect cancellation of the unbound mass = 12 top-quark masses by this binding energy. In other words the bound state is massless to the accuracy of our calculation. Our calculation is in disagreement with a similar calculation by Kuchiev et al., but this deviation may be explained by a phase transition. We and Kuchiev et al. compute on different sides of this phase transition.

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C. D. Froggatt, H. B. Nielsen. 2009-10-21. Remarkable coincidence for the top Yukawa coupling and an approximately massless bound state. https://doi.org/10.1103/physrevd.80.034033

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