Talk:Quark
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Alternative names for quarks
I don't think it's a good idea to include fringe names for the higher-generation quarks. Although there was some legitimate discussion about whether the top and bottom should be called truth and beauty, there was never any significant movement to name the strange anything other than strange. In fact, the term strangeness pre-dates the whole quark model. The extra names are simply confusing to the average reader; if they remain in the article at all, I suggest that they be moved to the History section. -- Xerxes 17:04, 2004 Jul 21 (UTC)
Disambiguation
At first when I saw the table of quarks with the up, down, etc., I thought it was a joke or crank. I continued to read the article, and I realized it wasn’t!! --Merovingian
It would be nice if this page was disambiguated. I would propose a format as seen in Cream. Any objections? --Bluetulip 11:25, 9 Mar 2004 (UTC)
It would probably be a good idea to create an explicit page for Quark (disambiguation) and move the extra bits from here to there.Done. --Phil 12:09, Mar 9, 2004 (UTC)
Quark, son of Keldar
I started an article on the Star Trek character Nog, nephew of Quark, then I clicked the Quark link and wound up here (I'll disambig at the Nog article today if I have time).
I'm wondering if maybe it would be better to move the disambiguation in this quark particle article up to the top of the page. I've seen pages on Wikipedia where the disambig is at the top, like the articles on Paris, Jupiter, etc., but I've also seen at the bottom, like on this one. Is their a standard policy on this? ShutterBugTrekker 16:48, 14 Jan 2004 (UTC)
CERN Experiment
The article now states: "One of the experiment in the CERN showed, that only 3 generation of the quarks exists. (From the resonance-width of Z boson.)"(sic) Which experiment, when? --Phil 14:09, Mar 8, 2004 (UTC)
- Cured. At least, reference given. --Andrew 05:28, Apr 23, 2004 (UTC)
Request from anon user
I have moved the following request from an anon user out of the article and placed it here for discussion. - Tεxτurε 05:12, 5 Aug 2004 (UTC)
- They are one of the two families of spin-1/2 fermions (can someone please clarify if this means spin=+1/2 or spin=-1/2)
Spin 1/2 particles can have either +1/2 or -1/2. In general, a spin-j particle can take on spin states anywhere from -j to j in increments of 1. -- Xerxes 17:53, 2004 Aug 5 (UTC)
Up & Down Quark Mass or Charge Problem?
Here are the masses and charges for quarks.
Up quark (1-5) (2/3) Down quark (3-9) (-1/3) Strange quark (75-170) (-1/3) Charm quark (1,150-1,350) (2/3) Bottom quark (4,000-4,400) (-1/3) Top quark (174,000) (2/3)
As you can see from this table, the quarks are arrayed in order from light to heavy, starting with the up quark. You should notice an irregularity with the up and down quarks compared to the others.
The top quark has charge of 2/3 and can decay into a bottom quark with a charge of -1/3. The bottom quark can decay into a charm quark with a charge of 2/3. The charm quark can decay into a strange quark with a charge of -1/3.
As you can see, a pattern is emerging (2/3, -1/3, 2/3, -1/3) which suggests that the next quark will have a charge of 2/3. But the next quark is a down quark with a charge of -1/3.
Could it be possible that either
an up quark has a charge of -1/3 and a down quark has a charge of 2/3
or
an up quark has a mass of 3-9 and a down quark has a mass of 1-5.
therefore restoring the pattern?
- No. Xerxes
How is it that these properties were attributed to these quarks in the first place?
- It's a complicated combination of experiment, theory and lattice calculations. See PDG Note on Quark Masses (http://pdg.lbl.gov/2004/reviews/quarks_q000.pdf) for an extended discussion. In particular, the u/d ratio can be determined in chiral perturbation theory as a ratio of sums of squares hadron masses. The physical value is around 1/2. Xerxes 15:44, 2004 Aug 27 (UTC)
The Brookhaven photograph
This is a bubble chamber photograph of Samios and Palmer, from early 1974. They believed at the time that it was a nakedly charmed baryon, but they were unable to eliminate all other hypotheticals, nor find a second example. Plus, they were using a new machine, and nervous about calibration. Even after the November Revolution, they were tentative about what they found. I presume that later discoveries have retroactively resolved the particle's identity.--192.35.35.34 17:11, 3 Feb 2005 (UTC)
The PDG entry on the Σc++ includes references, of course. The earliest is the one with the photograph. Its status was uncertain as late as 1982. I did not pursue the history of this particle any further.--192.35.35.36 23:37, 7 Feb 2005 (UTC)
Antiquark article
The Antiquark stub has been listed as VfD at Wikipedia:Votes_for_deletion/Log/2005_May_23#Antiquark. Vote Keep or Delete at this link. Irpen 22:34, May 23, 2005 (UTC)
Gluons
Should gluons be mentioned in this article? A gluon is a hypothetical neutral, massless particle believed to bind together quarks to form hadrons. → JarlaxleArtemis 01:44, Jun 2, 2005 (UTC)
- Gluons are not hypothetical; they are observed (albeit indirectly) in three-jet events. I don't think it's crucial to have a direct link to gluons in this article, since you can get to them by clicking any of the numerous links to hadron- and QCD-related articles. But if somebody can find a sensible place to mention them, it wouldn't be a bad idea. -- Xerxes 15:33, 2005 Jun 2 (UTC)
- They aren't hypothetical? It says they are hypothetical in both Webster's Dictionary and my school chemistry book. → JarlaxleArtemis 02:04, Jun 3, 2005 (UTC)
- Ah… perhaps the correct term is theoretical. → JarlaxleArtemis 00:59, Jun 8, 2005 (UTC)
- Yeah, just like electrons and evolution. -- Xerxes 17:48, 2005 Jun 8 (UTC)