A round shaped metal key ring with CERN logo engraved in a side and the Langragian equation in the other side.
The CERN logo is made up of two components :
The word "CERN", which is the acronym derived from the Organization's first official title : Conseil Européen pour la Recherche Nucléaire, or European Council for Nuclear Research. Today, our understanding of matter goes much deeper than the nucleus, and CERN's main area of research is particle physics. Because of this, the laboratory operated by CERN is often referred to as the European Laboratory for Particle Physics.
The interlaced rings, which are a simplified representation of the accelerator chain. The CERN’s current logo dates from 1968, when a decision was made to change the original one. Some 114 new designs were submited, many of which used CERN’s experiments as inspiration. The final design used the original lettering, surrounded by a schematic of a synchrotron, beam lines and particle tracks. Today’s logo is a simplified version of this.
The Langragian 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 third line describes how these particles obtain their mass from the Higgs boson, and the fourth line enables the Higgs boson to do the job.
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.
Metal, diameter: 4.2 cm.