 Higgs boson

The Higgs boson is the neutral radial excitation of the Higgs field about its vacuum expectation value.

In the single-doublet Standard Model this physical excitation is a spin zero excitation of a scalar field. Its mass depends on the Higgs potential, so the theory's gauge symmetry alone does not specify where to search. The Higgs boson discovery in 2012 tested the existence of a new particle resonance; establishing its detailed identity requires testing its interactions and spin as well.

The Higgs boson is a subatomic particle associated with the Higgs field, which is a fundamental field believed to give mass to other elementary particles through the Higgs mechanism. It was first predicted by physicist Peter Higgs and others in the 1960s as part of the Standard Model of particle physics, which describes the electromagnetic, weak, and strong nuclear interactions.

Initially there were mathematical reasons why people suspected that all boson needed to have 0 mass as is the case for photons a gluons, see Goldstone's theorem.

However, experiments showed that the W boson and the Z boson both has large non-zero masses.

So people started theorizing some hack that would fix up the equations, and they came up with the higgs mechanism.