The Higgs boson is an elementary particle in the Standard Model of particle physics. It is the excitation of the Higgs field, a fundamental field of crucial importance to particle physics theory first suspected to exist in the 1960s. Unlike other known fields such as the field, it has a non-zero constant value in vacuum. The question of the Higgs fields existence became the last unverified part of the Standard Model of particle physics and it also resolves several other long-standing puzzles, such as the reason for the weak forces extremely short range. Although the Higgs field is believed to permeate the entire Universe, in principle, it can be proved to exist by detecting its excitations, which manifest as Higgs particles, but these are extremely difficult to produce and to detect. On 4 July 2012, the discovery of a new particle with a mass between 125 and 127 GeV/c2 was announced, physicists suspected that it was the Higgs boson and this also means it is the first elementary scalar particle discovered in nature. The Higgs boson is named after Peter Higgs, one of six physicists who, in the 1964 PRL symmetry breaking papers, on December 10,2013, two of them, Peter Higgs and François Englert, were awarded the Nobel Prize in Physics for their work and prediction. Although Higgss name has come to be associated with this theory, in the Standard Model, the Higgs particle is a boson with no spin, electric charge, or colour charge. It is also unstable, decaying into other particles almost immediately. It is an excitation of one of the four components of the Higgs field. The latter constitutes a field, with two neutral and two electrically charged components that form a complex doublet of the weak isospin SU symmetry. The Higgs field is tachyonic, which does not refer to faster-than-light speeds, the Higgs field has a Mexican hat shaped potential with nonzero strength everywhere, which in its vacuum state breaks the weak isospin symmetry of the electroweak interaction. When this happens, three components of the Higgs field are absorbed by the SU and U gauge bosons to become the longitudinal components of the now-massive W and Z bosons of the weak force. The remaining electrically neutral component either manifests as a Higgs particle, or can couple separately to other known as fermions. Some versions of the theory predicted more than one kind of Higgs fields, alternative Higgsless models might have been considered if the Higgs boson had not been discovered. In this model, the forces in nature arise from properties of our universe called gauge invariance. The forces themselves are transmitted by particles known as gauge bosons, field theories had been used with great success in understanding the electromagnetic field and the strong force. The problem was that the requirements in gauge theory predicted that both electromagnetisms gauge boson and the weak forces gauge bosons should have zero mass
Nobel Prize Laureate Peter Higgs in Stockholm, December 2013
Photograph of light passing through a dispersive prism: the rainbow effect arises because photons are not all affected to the same degree by the dispersive material of the prism.