Mug with the Lagrangian equation and the CERN logo.

This equation neatly sums up our current understanding of fundamental particles and forces. It represents mathematically what we call the Standard Model of particle physics. The top line describes the forces: electricity, magnetism and the strong and weak nuclear forces. The second line describes how these forces act on the fundamental particles of matter, namely quarks and leptons. The last two lines describe the Higgs boson, and the mechanism by which particles acquire their mass.

Many experiments at CERN and other laboratories have verified the top two lines in detail. The existence of the Higgs boson was confirmed with the LHC in 2012. One of the primary objectives of the High Luminosity LHC is to study it in more detail and see if behaves as predicted by the last two lines..

If you want to know more and aren’t afraid of some physics, have a look at a very interesting paper published by three CERN guides.