In particle physics, it seems that all the work we do is devoted to finding out how to understand the original symmetry of our universe. If you have been following some of the latest entries in this blog, you know what I am talking about. If not, think about this, at the very beginning everything was very uniform (in the sense of very symmetric); in simplified words, there was probably just one “thing” with a single type of interaction (force). However, as the universe cooled down, it began a process of breaking this nice symmetry to the state in which we are today. I understand this is a little complicated to comprehend, and since this is a blog, I will try to share one of my oversimplified analogies; maybe it will help understand all this business about symmetries and the universe.
I sometimes think of our universe as a pot of glue made out of flour (try it, it is fun!) At the beginning, when you first prepare it with boiling water, you can nicely mix all the ingredients and you can tell it has a nice symmetric looking aspect. However, after you turn off the stove and let it cool down, little lumps start to appear (some of them here, some of them over there), breaking the symmetry of the mixture. If, after it has been cold for a while, you start warming it up again (increased temperature = more energy), you can see how the symmetry slowly gets restored as everything starts to gradually merge properly into the original state. You can actually follow, step by step, the restoration process.
In some sense, this is what we do with particle colliders. We warm up the “goo” to recover the symmetries that have been hidden for billions of years in the hope that we can understand the original state. We have made a lot of progress so far, and the LHC is just one (very important) step above in temperature (energy).
Edgar Carrera (Boston University)
