Mass is one of the most important concepts in science, but a full explanation of where it comes from eluded physicists for decades.
They recently worked it out. To find the answer, you need to look into the world of quantum mechanics.
Quantum mechanics found that within protons and neutrons, there is a whole new series of particles like quarks, gluons, and bosons. This framework is called The Standard Model.
Gluons are part of this model, and they make other particles (quarks) stick together. Their energetic movement create most of an object’s mass. But even when you account for the action of gluons, there is still a remainder of mass that is not accounted for, and this was the mystery that baffled scientists for decades.
It turns out it comes from a thing called the Higgs field.
It requires a bit of a backstory. Quantum field theory discovered that the universe is made up of several invisible fields (like the electromagnetic field) and everything in it interacts with them in one way or another. The Higgs field works the same way.
Quarks are constantly running into the Higgs field, which slows them down like a tennis ball skimming across water in a pool. This restriction of the movement of quarks is what gives them the rest of their mass.
Before this theory could be confirmed, the ‘Higgs Boson’ had to be discovered.
It’s the excitation of the underlying Higgs field, like how the photon is the excitation of the electromagnetic field.
The Higgs boson is one of the most difficult particles in quantum mechanics to detect, which has made it one of the ‘final pieces of the puzzle’ in experimentally verifying the Standard Model. As such, it’s been the white whale of particle physics for over 40 years.
In a display of the power of our theoretical models, the Higgs boson was identified for the first time in 2013 in CERN’s Large Hadron Collider after an enormous international effort.