It must be nice having a Large Hadron Collider to mess about with. One day you're just minding your own business, running lead-proton collisions for reference in order to subtract out background noise from the lead-lead collisions that you actually care about, and then poof, you somehow create a new form of matter called a color-glass condensate. Nice.
Color-glass condensates have never been seen before, but the idea is that they'd exist when you've got a particle like a proton moving very, very close to the speed of light. When something is moving that fast, it's experiencing some weird stuff according to the theory of relativity. While everything's normal for the proton, anyone going not so fast and observing it (i.e. us and the LHC's sensors) will notice two things: first, the proton will be squished up along the direction that it's travelling in (length contraction), and time will have also slowed down for it (time dilation), both of which are relativistic effects.
So we've got a squished-up, slowed-down proton, and if you crack it open (by smashing it into a lead ion like the LHC does), it disintegrates into its component parts, which consist of three quarks (two up quarks and one down quark) along with some gluons, which are manifestations of the strong force that keeps quarks stuck together (which is why they're called "glue"-ons). It's these high-speed gluons that get together to form a color-glass condensate, and when two of these condensates smash into each other, you get a quark-gluon plasma, which is likely what the beginning of the universe was made of. Whoa.
Anyway, let's figure out why a wave of speedy gluons is called a "color-glass condensate." Both the quarks and the gluons come in colors, which aren't colors like we think of them, but rather names for a sort of charge that comes in three different varieties (red, green, and blue), and that's where the "color" part of the "color-glass condensate" comes from. The "glass" part refers to the fact that you've got this bunch of gluons that normally act all disordered like a liquid, but because of time dilation, we observe them moving very slowly and sticking together like a solid. Glass was long thought to be a solid that acted like a liquid over long time scales, which is why the name is used here. The last thing, "condensate," just says that the gluons are extremely dense. You may have heard of a Bose-Einstein condensate, which is a stupendously dense cloud of atoms that can slow light down to a crawl. Same idea.
The interesting bit about all this (besides the whole new form of matter thing) is that we may be able to use color-glass condensates to help us figure out how matter is arranged inside the particles that we're smashing together. Based on these tentative results, the LHC will run more lead-proton tests in January to verify that they really are seeing what they think they're seeing. LINK
Via MIT
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