Talk:Color confinement

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"Thus the force experienced by the quark remains constant regardless of its distance from the other quark. Since energy goes as force times distance, the total energy increases linearly with distance."

I was under the impression that gluons are represented as springs in Feynman diagrams because the force felt between two quarks roughly follows Hooke's Law F = -kx (or F = kx if k is taken to be negative) and so is roughly proportional to some constant times the distance. This would obviously mean that U = (+/-)kx^2, or that the total energy increases quadratically with distance. Am I incorrect in this impression? Or would someone with greater experience correct this? (August 23, 4:49 pm UCT)

The article is correct. See (for example, just randomly) the recent paper QCD potential as a "Coulomb-plus-linear" potential -- Xerxes 02:42, 2004 Aug 24 (UTC)

More intuitive: The energy stored in a flux tube between two (static) quarks doubles as one doubles the distance between the two quarks (neglecting a possible "string breaking"), hence the force is constant. There is no such a "internal" structure as in a spring. A string is almost a spring, but just almost :-) --129.132.1.35 10:02, 1 Sep 2004 (UTC)

Nobody answered this person's question, the question again is, "Am I incorrect in this impression?" His alternative question followed from that, and that question is, " Or would someone with greater experience correct this?" - 'this' refers to the person's impression of the article, not the correctness of the article, and not your impression of the article. The article in wikipedia says, "Thus the force experienced by the quark remains constant regardless of its distance from the other quark." - regardless of distance???? That is simply wrong. Because the force depends on the distance (if it is small, large, or something in between). I'm going to see if I can word things better than they currently are.Kmarinas86 22:33, 28 June 2006 (UTC)

[edit] strange matter

Wouldn't something like strange matter violate confinement? -- Natalinasmpf 12:15, 5 November 2005 (UTC)

No, strange matter has extremely high density. Confinement restricts how far quarks can move away from one another. Strange matter has so many quarks in so little space that they do not need to move far from one another. -- Xerxes 17:59, 5 November 2005 (UTC)

[edit] mistake

Something is wrong here:

> Thus the force experienced by the quark remains constant regardless of its distance from the other quark.

> The force between quarks increases as the distance between them increases, so no quarks can be found individually.

One of these statements is wrong. Which one?

They're both correct at different scales. As quarks separate, the force between them initially increases and then becomes constant. Could be worded more clearly perhaps. -- Xerxes 22:12, 13 December 2005 (UTC)

I've heard that, at some range, the attractive force between quarks increases linearly with distance (i.e. dF / dx = constant). However, when that is true, that would mean that force*distance would be quadratic in nature, like elastic potential energy (i.e. .5kx²). In contradiction to this, there is the coloumb+linear potential, which does not appear to have the property of linearly increasing force. [[1]] In fact, the decreasing of the slope in the line graph of such a potential, suggests to this layman that force decreases with distance (which is obviously wrong). [[2]] Somebody please clarify this...Kmarinas86 21:54, 28 June 2006 (UTC)

This article, the quarkonium article and the linked images indicating Coulomb plus linear are correct. -- Xerxes 22:29, 28 June 2006 (UTC)

Explain to me how the slope for positive potential decreases with distance r (as in -1/r+r) and yet the force be increasing or remain constant. This is what I don't get. A binding force which is increasing with distance will imply a binding energy which increases with distance in a non-linear increasing-slope fashion, whereas a binding force constant with distance will have a linearly increasing binding energy. I thought potential and energy are very related. Is it the case the potential and energy are not proportional? I've never heard of such. Why is the term "binding energy" avoided and/or not used in the case of confinement. What is with the confusion between linearly increasing force and linearly increasing energy as distance increases linearly? Why do some interested people even have to be confused about this, when things are supposed to be said in a straightforward manner? Why do many people have the impression of "spring constants" even if they are aware that there exists a difference between a "string constant" and a "spring constant" Please answer the questions, only if you can explicity, thanks...Kmarinas86 23:12, 28 June 2006 (UTC)

Why do people write like that? Concerning these two sentences, difference in context is indistinguishable as far this this single article is concerned, thus the statements, though correct according to some, are contradictory. Why can't they just say it in a more straightforward manner that doesn't look like a hodge podge? This is ample proof that the article is not clear as it ought to be. Show me the formula that corresponds to the force which increases directly proportional to energy AND distance simulatanously. If you tell me that force and energy are the same quality in the context of the "linearly increasing" nature of the confinement, you'll make absoultely no sense to me, unless you back your claims.Kmarinas86 23:32, 28 June 2006 (UTC)

Of course the problem is that the analitic expresion for this force has not been given anywhere yet, we have separate indications of asymptotic freedom (force decreasing fast at short distances) and confinement (huge force at large distance). Quarkonium is just a model (a good one) extracted from approximations to QCD, but no straigh QCD thing. Perhaps a detailed aricle should give some quantitative data from lattice simulations Arivero 07:17, 29 June 2006 (UTC)

On other hand, a string model of quarks has constant string tension, thus constant force. Arivero 07:24, 29 June 2006 (UTC)

[edit] Quark deconfinement now redirects here

Quark deconfinement (presumably referring to what happens in relativistic heavy ion collisions) now redirects here. Therefore it would probably be good to add a section on this topic. Any experts out there? HEL 02:16, 5 November 2006 (UTC)