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Are there any technical limitations (theoretical or technological) that prevent quark based colliders? ie. Colliding two quarks together.

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Quarks in isolation cannot be observed. A basic "axiom" of particle physics as we know it is that all singular isolated particles must be "colorless" (see So it turns out that you can only have quarks bound together to form hadrons (either 2 or 3 quarks, for mesons and baryons respectively). So that seems to rule out a quark collider (although perhaps there are speculative theories as to how the aforementioned "axiom" can be broken). – user758556 Jun 29 '12 at 23:46
Just to get behind user758556 -- so far the best we've been able to do is create a quark-gluon plasma and study this as a phase of matter. Experiments like PHENIX at BNL whip gold ions around and smash them together to 'melt' the nucleons and release the quarks and gluons inside. They quickly decay and we try to infer properties of the QGP by observing the particles which are produced as it all cools. No one knows how to steer quarks b/c we don't know enough about the strong interaction to control them. – unclejamil Jun 30 '12 at 0:31
Above a few GeV in CoM energy and momentum transfer you looking predominately at parton--parton reactions, though in that regime the nuclear or nucleon context is still muey important. At Tevetron ot RHIC or LHC not so much. Of course for physics that is less QCD messy you go to lepton colliders (i.e. SLAC, LEP, LEP2, and the much envisioned ILC). – dmckee Jun 30 '12 at 1:30

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The success of the Standard model in organizing our particle data is also based on the strong interaction SU(3) color, which displays asymptotic freedom.

In physics, asymptotic freedom is a property of some gauge theories that causes bonds between particles to become asymptotically weaker as energy increases and distances decrease.

To get free quarks so that you can have quark-quark scattering you either"

go to very small distances, and it is impossible to do a controlled scattering at those small distances,


very large energies, energies that prevailed before nucleosynthesis after the Big Bang. Again there is no possibility of carrying controlled scattering experiments.

We study the collective behavior of quarks in the quark gluon plasma at current accelerators,

Although the results have yet to be independently verified as of February 2010, scientists at Brookhaven RHIC have tentatively claimed to have created a quark-gluon plasma with an approximate temperature of 4 trillion degrees Celsius.[4]

As already mentioned, three new experiments running on CERN's Large Hadron Collider (LHC), on the spectrometers ALICE,[5] ATLAS and CMS, will continue studying properties of QGP.

It is a matter of ongoing research, and will give a handle by deciphering the statistical behavior of quark quark scattering in the plasma.

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If I may ask a semi-layman question. Can this QGO be phase locked by introducing an extremely high pressure containment before the cooling process begins? – Argus Jun 30 '12 at 10:17
Ion plasma is contained and manipulated by magnetic fields. There is nothing analogous in the strong force that could contain the colored quarks. – anna v Jun 30 '12 at 10:42

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