The last couple of weeks have seen a number of articles about the Higgs Boson (or the God particle as the press loves to call it). This post takes a look at why physicists think it exists and why they are so keen to find it.

Problematic theories

A good starting point is the Standard Model of particle physics.  The Standard Model explains how three of the four fundamental forces of nature operate (the electromagnetic, the weak nuclear force and the strong nuclear force).  The standard model is phenomenally successful and is one of the most accurate theories of science around.

However a “natural” formulation of the standard model would predict that particles have no mass.  This is something of a problem for a theory when quite obviously everyday matter does indeed have mass.

The solution to this problem is the Higgs mechanism.  This postulates the existence of the Higgs field.  Particles travelling through the Higgs field are slowed down.  This “friction” from the Higgs field is what gives them mass. Incorporating the Higgs mechanism into the Standard Model explains where mass comes from but it also has the side effect of predicting a new particle.  The Higgs boson.

Higgs = Nobel. Maybe.

The Standard Model predicted the existence of a number of other new particles, such as the W and Z bosons.  However these were experimentally confirmed to exist more than 20 years ago.  Had we found the Higgs boson first then we’d probably all be talking about the W and Z bosons being the holy grail of particle physics.  Nevertheless the Higgs is the final piece of the puzzle.

As a result physicists desperately want to find the Higgs as the final confirmation of the Standard Model (the prospect of a Nobel prize for the discoverer probably doesn’t hurt either).