That’s how this TED video on the Higgs boson begins. I say two guys… It’s more like one physicist working on the Large Hadron Collider at CERN – the European laboratory for Particle Physics – aka Dave Barney, and a Blues singer, aka Steve Goldfarb, in the guise of a pink slug…
Anyway, Dave asks Steve about the Higgs boson – something physicists have discovered with the LHC – and Dave begins to explain…
The Higgs boson is a fundamental particle.
Not just any fundamental particle, because the Higgs boson is one of two types of fundamental particles and it is a particular game-changer in the field of particle physics, proving how particles gain mass.
This particle is special because it means that the Higgs field might really exist. The Higgs field was named after Peter Higgs, its discoverer, although many other physicists contributed to the idea.
The Higgs field is a hypothetical, invisible kind of force field that pervades the whole Universe.
“If it pervades the whole Universe, how come I have never seen it? That’s a bit strange.” asks Steve the slug candidly.
“It’s not that strange” replies Dave. “Air is invisible, but we can detect its presence with sophisticated equipment.”
The fact that we cannot see something makes it a bit harder to determine whether it’s really there or not. But what the Higgs field does is really special, because it is thought to be responsible for giving mass to elementary particles.
What’s an Elementary Particle?
An elementary particle is what physicists call particles that have no structure. They cannot be divided… as far as we know. The building blocks of the Universe.
Atoms are made of smaller components – neutrons, protons, and electrons. And whereas electrons are fundamental particles too, neutrons and protons are made up of other fundamental particles – quarks.
Our current state of understanding is called the Standard Model.
There are two kinds of fundamental particles:
fermions make up matter
bosons carry forces.
Physicists can measure the mass of those particles. But until now, they did not know where the mass was actually coming from or why particles have the masses they do.
When a particle passes through the Higgs field, it interacts with it and gets mass. The more it interacts with it, the more mass it has. If there were no Higgs field, the Universe would not exist at all. There would be no galaxies, no stars… Nothing at all.
What Quantum Mechanics teaches us is that all particles are excitations of force fields.
The Higgs boson is an excitation of the Higgs field. Finding the Higgs boson is evidence that the Higgs field exists.
Particle Physics is a voyage of exploration. Just as Columbus mistakenly thought he had discovered a new route to India when his expedition landed on American shores, particle physicists keep finding new things, even though they are not always what they were expecting to find in the first place.
Physicists now need to ensure that the boson they have found is indeed the Higgs boson. The key to this confirmation is gathering even more data to determine its properties.
This newly-found boson is very short-lived before it decays into lighter and more stable particles. By measuring these particles, physicists learn about the properties of the boson.
The Standard Model
The Standard Model predicts how often and in what way the Higgs boson decays into lighter particles. This elementary particle may be the one predicted by the Standard Model, or it may turn out to be something entirely different that fits into other possible theoretical models. And if it does, it may turn out to be even more exciting.
Because scientific progress is made by replacing antiquated models with new ones, if their predictions are a better match for actual observations.
And as Dave says, finding the Higgs boson is just the beginning…