With all the excitement about the Higgs boson, it seems like a good time to think about the other bosons that we know about. The Standard Model of particle physics contains a total of four bosons (not counting the theoretical Higgs). These bosons are considered force carriers, because they communicate the three fundamental forces of physics that are explained by quantum physics. The bosons associated with these three forces are:
There are four bosons because the W boson and Z boson work together to mediate the weak nuclear force.
In addition to the above bosons, theories of quantum gravity also propose another type of boson, the graviton, which would mediate the gravitational force. To date, however, this boson has not been confirmed.