Seeing is Believing


By Sara Nedley

For the last 60 years, the Standard Model of particle physics has been used to understand the fundamental building blocks of matter, with one important piece to the puzzle missing. Although the Standard Model is employed as the “guide” for understanding particle physics, the theory is missing definitive proof of the particle that explains how particles get their mass. Physicists know that an elementary particle must somehow interact with other particles to give them mass, yet the particle has not been proven to exist. However, physicists have recently moved closer to finding that very elusive last piece to the puzzle known as the Higgs boson.

The Building Blocks of Life

Sometimes referred to as the “God” particle, the Higgs boson is thought to give mass to all matter. Currently the mass of the Higgs boson remains unknown, and without that knowledge it is not understood how other particles acquire mass. Physicist Peter Higgs first used the Higgs boson to explain how particles obtain mass. He proposed that a “Higgs” energy field exists everywhere in the universe and as particles move within it, they interact with and attract Higgs bosons. The greater the amount of Higgs bosons that cluster around the particle, the greater the resultant particle mass.

Big Discoveries, One Particle at a Time

The Higgs boson is the proof needed to determine that there is a Higgs energy field. Scientists at the European Organisation for Nuclear Research (CERN) have been using the Large Hadron Collider (LHC) to create Higgs bosons through particle acceleration experiments. Two major experiments, known as ATLAS (A Toroidal LHC Apparatus) and CMS (Compact Muon Solenoid), observe the collision of protons that have been accelerated to nearly the speed of light. When particles collide, they can turn into energy and that energy can then create new types of matter. In Dec. 2011, researchers announced that both the ATLAS and CMS experiments have turned up signs of the Higgs boson’s existence. Like all discoveries and revelations about the fundamentals of nature, the future implications of the discovery of the Higgs boson remain unclear. Finding the Higgs boson will not reveal everything about how the universe works, but it gets us one step closer to a more complete puzzle.

Classroom Discussion

  • What other particles are included within the Standard Model of particle physics?
  • What are the masses of protons, neutrons and electrons? How do they compare to one another?