If we imagine for a moment that the weak interactions of the confined quarks are turned off, the resulting masses of the three generations average to ~3.5, ~700, ~88,000, and are still created, presumably, by the Higgs Yukawa terms in the SM Lagrangian. When the quark weak interaction is turned back on these confined generation masses split by ~70%, ~170%, and ~200% respectively. Don't these magnitudes conflict with idea of the "weak" interaction and the size of its coupling constant? Some bizarre effect of Higgs? Has someone somewhere calculated and explained this?

  • $\begingroup$ I think that your question would get more attention if you included a derivation or a source for the numbers in the question (3.5, 70%, etc.). $\endgroup$
    – sasquires
    Apr 17, 2021 at 20:00
  • $\begingroup$ The source of the data is the masses of the six flavors of quarks given by the Particle Data Group's publicly available and widely used annual summary of high energy physics particle data. Nothing added. $\endgroup$ Jun 12, 2021 at 19:13
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    $\begingroup$ I also have no idea what you mean by confined mass splittings generated by the weak force. Please show how you get these numbers, I would like to know! $\endgroup$ Jul 26, 2021 at 3:26
  • $\begingroup$ The average of the top and bottom quark masses is ~88k, and their diff is ~200% of the average, and similarly for the others, but, as noted below, the question is probably a totally unphysical one. $\endgroup$ Jul 28, 2021 at 1:24

1 Answer 1


There might be a misconception here. The masses of all six (current) quarks are due to Yukawa couplings to the Higgs doublet following SSB: the mass split within each SU(2) doublet is never due to the (gauge) weak interactions, and is perfectly consistent with the symmetries of the SM.

The Higgs mechanism and gauge couplings simply don't enter in the mass terms dispositively. All six Yukawa couplings are independent and mysterious in the SM. The down and the up members of a(n arbitrary) generation's quark doublet get their masses by SU(2)×U(1) invariant couplings to Higgs or conjugate Higgs doublets, so the v.e.v. is either upstairs or downstairs.

I suspect you are barking up a wrong tree.

  • $\begingroup$ I agree. I've recently come to a similar conclusion. It simply doesn't make sense in the SM to talk about mass at all without the weak interaction, SSB, and the Higgs, which has only the weak couplings. $\endgroup$ Jul 28, 2021 at 0:58

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