10 years of Higgs boson

Ten years ago, scientists announced the discovery of the Higgs boson, which helps explain why elementary particles (the smallest building blocks of nature) have mass.

Higgs Boson:

• Physicist Peter Higgs predicted the Higgs boson in a series of papers between 1964 and 1966, as an inevitable consequence of the mechanism responsible for giving elementary particles mass.
  • This theory suggests particle masses are a consequence of elementary particles interacting with a field, dubbed the Higgs field.
  • And according to the same model, such a field should also give rise to a Higgs particle — meaning if the Higgs boson wasn’t there, this would ultimately falsify the entire theory.
• They are smaller than an atom and the wavelength of visible light, so the only way we can detect and observe their behaviour is by smashing the atomic nucleus of particles together at intense speeds (close to the speed of light), which generates vast amounts of exotic particles that are only created at high energies.
  • These collisions resemble the conditions physicists believe existed during the time of the big bang.
• Thanks to particle accelerators like the Large Hadron Collider, the Relativistic Heavy Ion Collider and the (now defunct) Tevatron circular particle accelerator, physicists have made a lot of progress in designing a “theory of everything.”
• This theory postulates how all the subatomic particles in the universe operates and how they interact to comprise the Universe as we know it.
• One of the most complete models that comes anywhere near producing a “theory of everything,” is the Standard Model of Fundamental Particles and Interactions, which describes how particles and forces interact.

Discovery of Higgs Boson:

• In 2010, the Large Hadron Collider (LHC) began colliding protons with seven times more energy than the Tevatron.
  • The Tevatron collided protons (which, along with neutrons, make up the atomic nucleus) and antiprotons (nearly identical to protons but with opposite charge).
• Finally, on July 4 2012, two independent experiments at CERN had each collected enough data to declare the discovery of the Higgs boson.
• In the following year, Higgs and his collaborator François Englert won the Nobel prize “for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles”.

What have we learned since the Higgs boson discovery?

• Discovering the Higgs boson was just the beginning. In the ten years since, physicists have examined how strongly it interacts with other particles, to see if this matches theoretical predictions.
• Interaction strength can be measured experimentally by looking at Higgs boson production and decay: the heavier a particle the more likely the Higgs boson is to decay into or be produced from it. Interaction with tau leptons was discovered in 2016 and interaction with top and bottom quarks in 2018.
• But there is much more still to learn about this elusive particle.