One of the most exciting things about using giant particle accelerators like the LHC to learn more about the building blocks of the Universe is the fact that it's often very difficult to predict what you're going to get when you start smashing particles together at astronomical speeds. You kinda just have to go for it and once you've got something, work backwards from there, using maths to figure out what you created and how. This is exactly what happened back in October, when scientists in Vienna announced the discovery of the glueball - a particle that consists of no mass, but is made entirely of nuclear force.
Glueball might sound like a pretty dumb name, but it actually suits this enigmatic little particle really well. As the video by SciShow above explains, it's a particle made from gluons - much smaller, sticky particles that are responsible for keeping an atom's nucleus from flying apart because all the protons keep repelling each other. And the fascinating part is that these gluons are able to hold everything together even though they contain no mass themselves.
If the discovery of these particles is confirmed, we have more evidence to suggest that the standard model of physics - on which we base our entire understanding of how physics in the Universe actually works - is, in fact, correct.
Working backwards from the results of some serious particle smashing is how physicists discovered the Higgs boson, but in that case, they knew what they were looking for. It was just a case of sifting through incredible amounts of data for years to find signs of its appearance. To find a glueball, on the other hand, physicists have to sift through just as much data, but this time, they're not exactly sure what the thing they're trying to find even looks like.
What we do know is that glueballs are made of gluons, and they're kept together using what's known as strong force. The name is a bit of an understatement, because the strong force is 100 times stronger than the electromagnetic force that keeps the electrons in place inside atoms, and way, way stronger than the force of gravity.
Knowing this, and where gluons and glueballs theoretically fit into the standard model of physics, is how scientists are trying to find definitive proof for their existence. But it's not as simple as just smashing together a bunch of protons and antiprotons - a combination that's predicted to produce gluebulls. Watch the episode of SciShow above to find out, and if you're feeling a bit lost, here's a Physics Girl episode to help you get up to speed: