# Is color confinement detected?

I'm a graduate student studying QFT. I'm quite interested that is color confinement detected or proved? (both directly and indirectly) Or it is just an assumption?

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I thought confinement was only detected. Isn't one of the millennium prizes to prove confinement? –  Joe Joe Jan 19 '13 at 5:14
@Joe Joe: the prize is only for the mathematical standard of proof. The physics standard of "proof" is quite a bit lower. –  Peter Shor Jan 19 '13 at 16:09

## 1 Answer

Here is an experimentalist's answer.

Color confinement is a theoretical concept arising from the plethora of experimental observations that are summed up theoretically in the Standard Model. We have no free quarks or gluons, we do have quark jets and gluon jets. So confinement as predicted by the SU(3)xSU(2)xU(1) SM is consistent with all the existing data.

One has to keep in mind that a theory applying to experimental data can be falsified,or can be found consistent with the data; but consistent is not proof, it is a temporary validation.

A theory of course has axioms and mathematical proofs, so a theorist should answer whether the theory of QCD allows unconfined manifestations of color. These should be in phase spaces not explored by present experiments.

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Unconfined 'manifestations of colour' (i.e. coloured one-particle states, for example) would not be gauge invariant, so they cannot exist in QCD. –  Vibert Jan 19 '13 at 11:20
@Vibert . thanks. what about within a quark gluon plasma , as in big bang ? –  anna v Jan 19 '13 at 11:23
Strictly speaking, it is only predicted by $SU(3)$, not by the whole symmetry of the Standard Model. –  Frederic Brünner Jan 19 '13 at 12:38
@FredericBrünner well, it is all three together that describe all data consistently , quarks and all. –  anna v Jan 19 '13 at 12:50
True, but the mechanism of confinement is specifically related to $SU(3).$ –  Frederic Brünner Jan 19 '13 at 12:54