The Higgs boson has been the talk of the town in recent days, with two experiments, ATLAS and CMS, at the Large Hadron Collider by CERN reporting their discoveries of a new particle. But what is the Higgs and what’s so special about it?
Particle Physics 101
Particle physics is the branch of physics that studies the fundamental building blocks of the universe. At the beginning of the 20th century, the electron and atom were being discovered; these discoveries changed how the world looked at the universe – the beginning of modern chemistry.
The later discoveries of the—even smaller—proton and neutron gave us the ability to split the atom, giving more insights into the building blocks of the universe. These discoveries eventually lead not only to the atom bomb, but also many of the life-saving radiation-based technologies used in modern medicine.
Old school to New school
The modern picture of the fundamental particles became known as the Standard Model of Particle Physics. In this model, 12 fundamental particles of matter were proposed, whose interactions were mediated by another kind of particle.
Unfortunately, there was a problem with the model. The only way to construct such a model so that it was self-consistent is if all of the particles are massless, something that we know not to be true in Nature. Given that the model almost perfectly describes all the other properties of the particles, new questions arose – what is the origin of their mass, and how can we integrate it into our model?
Enter the Higgs boson
To give our particles mass, the Standard Model was revised. This revision suggested that the fundamental particles don’t have mass as an inherent property. Rather, mass is a consequence of their interaction with another particle – the Higgs boson.
Of course, when the Standard Model was finalised in the mid-1970s, the Higgs boson had not been discovered, and no-one knew what energies would be needed to create one. Therefore, many particle accelerators were designed, built, and run, to slowly narrow down the possible energy scales at which the Higgs boson could be created and viewed.
Construction began on the Large Hadron Collider in 1998. It was built as a huge—and expensive, with a budget of €7.5 billion—experiment to confirm the existence of the Higgs boson. Construction on the LHC took 10 long years, involving collaborative efforts of over 100 countries and over 10,000 scientists and engineers!
Experiment after experiment was conducted, smashing together particle after particle. Data flowed out and countless man hours were spent crunching the numbers. Throw in a few shed blood, sweat and tears, and the Higgs boson was finally discovered.
Thank God-particle they discovered it
However, if instead the experiments had ruled out the existence of the Higgs, it would be back to the drawing board for us particle physicists to formulate a new mechanism for the origin of mass. Thankfully, the experiment paid off and we now have an almost complete picture of the Standard Model of Physics. As we continue probe the universe to its smallest scales, who knows what new technologies and possibilities will arise.