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Wikipedia:Reference desk/Archives/Science/2023 December 10

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December 10

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Why is the top quark more massive than the Higgs boson?

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I only have a beginner level understanding of particle physics and such, but I was wondering why the top quark had more mass than the Higgs boson? Shouldn’t the Higgs boson be the most massive particle there, since it’s the quantum excitation of the Higgs field? UniversalAlien (talk) 00:19, 10 December 2023 (UTC)[reply]

The Higgs mechanism only explains the massivity of some gauge bosons, which include the quarks but not the Higgs boson itself, since it is a scalar boson. No way is currently known of calculating the masses of the various elementary particles from accepted underlying theory such as the Standard Model and QCD, except that those moving at the speed of light are massless. Theses masses can therefore only be determined by experimental measurement and we have no clue why they are as they are found to be.  --Lambiam 11:52, 10 December 2023 (UTC)[reply]
Lambiam, if I can parlay someone else's question into a query of your take on a tangentially related topic: are you someone who finds it worthwhile to ponder the hypothetical significance of dimensionless constants, e.g. the fine structure constant? As a comparative layperson, I find both extreme positions—that such questions are axiomatically meaningless, or that they are of singular importance and most likely "hold the key" to the door to further understanding—to be unsatisfying, but beyond that I can't decide where I fall. Remsense 00:46, 11 December 2023 (UTC)[reply]
It is conceivable that some future theoretical physicist develops a testable theory of the quantum foam of the vacuum from which the value of the fine structure constant emerges as the limit of a summation over an infinitude of Feynman diagrams. So there might be an answer to question why has the value that is has. An open-minded scientist would not assert that the question is necessarily meaningless, but one should accept the possibility that there is no explanation other than that it is where it happened to become frozen in some symmetry breaking process.  --Lambiam 09:06, 11 December 2023 (UTC)[reply]
The masses of the fermions, gauge bosons, and the Higgs particle itself get turned into various coupling constants with the Higgs field, like you can see in Section 11.2.1 of the 2022 PDG update here: [1]. This doesn't tell you what the values of the coupling constants should be, so (as Lambiam mentioned) it also doesn't tell you what the masses will be. It gets more complicated because the masses you measure in an experiment get modified by "quantum corrections" because of interactions between the various fields. The Higgs doesn't have to be the most massive, but the seemingly most "natural" outcome would be for all the masses to be similar but not identical. The thing that seems very surprising, then, is that most of the other fermions are so much lighter, especially the neutrinos. This is something people are trying to understand, building models, testing the masses vs measurements of the coupling constants themselves in collider experiments [2]. --Amble (talk) 18:18, 11 December 2023 (UTC)[reply]

Tadpoles that never grew up

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I remember watching an arte documentary once about alluminium. A German-speaking researcher was interviewed there who showed in his laboratory that tadpoles apparently did not undergo metamorphosis when exposed to aluminium. Does anyone know about this study? 2A02:8071:60A0:92E0:290F:A41:F8B0:B100 (talk) 12:34, 10 December 2023 (UTC)[reply]

A Google scholar search for the obvious keywords gives lots of hits, of which a well-cited article was this one from 1986. That probably isn't your researcher if the documentary was a recent one. In particular, it says the tadpoles took longer to undergo metamorphosis, not that they never did, but that may depend on the aluminium dose. Mike Turnbull (talk) 15:04, 10 December 2023 (UTC)[reply]
Their growth was aluminum foiled. ←Baseball Bugs What's up, Doc? carrots18:25, 10 December 2023 (UTC)[reply]
Witzelsucht is a sad condition. --jpgordon𝄢𝄆𝄐𝄇 21:18, 10 December 2023 (UTC)[reply]
Only to its victims. ←Baseball Bugs What's up, Doc? carrots20:09, 11 December 2023 (UTC)[reply]

Can stratospheric water vapour be measured through ice cores?

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That is, prehistoric stratospheric water vapor which tends to end up in Antarctic ice cores. Jo-Jo Eumerus (talk) 17:00, 10 December 2023 (UTC)[reply]

I don't think there is a way to determine whether an H2O molecule in Antarctic ice spent some time in the stratosphere after evaporation before ending up in the ice.  --Lambiam 23:16, 10 December 2023 (UTC)[reply]
Yes, ice cores can be used to indirectly infer past stratospheric water vapor levels through analysis of oxygen isotopes in the ice.[3] -- 136.54.106.120 (talk) 02:24, 11 December 2023 (UTC)[reply]