The weather is looking good, so it’s a perfect day to take a trip to the zoo. Which zoo, you ask? In preparation for the deeper exploration into CERN‘s research next week, it seems appropriate to visit the Particle Zoo!
If only there were an actual zoo that exhibited particles though. I’m sure it would be teeming with visitors aspiring to learn about the building blocks of our universe. Nonetheless, we’ll just have to make do.
The most widely accepted theory concerning matter at a fundamental level is the Standard Model, and is one of the theories that CERN is currently testing out. In its simplest depiction, the Standard Model lists the seventeen fundamental particles that our entire universe consists of and uses to interact. That’s right, you heard me. Only seventeen.
The quarks and leptons are the particles that make up the matter in our universe; they are the stuff that you can ‘feel’ for lack of a better word. As far as we know, all matter is made up of any combination of quarks and leptons.
The gauge bosons are force carriers – a force is transmitted by exchanging a gauge boson between two particles. Each gauge boson is designated to one of the four fundamental forces. You would think that each fundamental force gets one gauge boson, but surprisingly the weak nuclear force gets both the Z and W bosons. The force carrier for gravity has not yet been found, and it’s possible that such a particle does not exist, given the recent discovery of gravitational waves.
Finally, we have the Higgs boson, which caused a lot of commotion when its existence was confirmed in 2013. The reason is that it that gives mass to the other particles (I won’t go into detail about how it does so, but you should appreciate its magnificence anyway).
So there you have it. Those are the fundamental particles. But how boring would it be if that was all the particles we knew about? We can pick and mix them together to create new composite particles. We’re now heading to the composites exhibition of the zoo!
Hadrons are particles that consist of quarks; in fact quarks hate loneliness so much that it is impossible for quarks to be isolated. There are two types of hadrons: baryons and mesons.
Baryons consist of three quarks or three antiquarks (ooh, antimatter); examples of baryons include the famous proton and neutron which are found in the centre of every atom. Mesons consist of a quark-antiquark pair.
As you can see, there a countless number of possible combinations of quark groups, leading to very exotic particles and exotic atoms (yes, that’s the scientific term) that are assigned weird and wonderful Greek letters. There was genuinely a time when CERN was discovering at least one new particle every week!
We can’t afford to enter the exotic exhibition of the zoo sadly (i.e. I’m too lazy to write about them), so we’ll leave it at that.
No particles were harmed in the writing of this post. #ParticleLivesMatter