规范玻色子

规范玻色子是传递基本相互作用的媒介粒子，它们的自旋都为整数，属于玻色子，它们在粒子物理学的标准模型内都是基本粒子。

规范玻色子包括：

胶子 - 强相互作用的媒介粒子，自旋为1，有8种
光子 - 电磁相互作用的媒介粒子，自旋为1，只有1种
W 及 Z 玻色子 - 弱相互作用的媒介粒子，自旋为1，有3种
引力子 - 引力相互作用的媒介粒子，自旋为2，只有1种

标准模型预言的另外一种玻色子——希格斯粒子，不属于规范玻色子。

标准模型的规范玻色子

粒子物理学的标准模型给出了三种标准波色子：传递电磁相互作用的光子;传递弱相互作用的W及Z玻色子，和传递强相互作用的胶子。 ^[1]

单个胶子在低能状态下无法存在，因为他们的色荷性质，并且必须服从夸克禁闭。

规范玻色子的多样性

在量子化的规范场论中标准玻色子是规范场的量子。Consequently, there are as many gauge bosons as there are generators of the gauge field. In quantum electrodynamics, the gauge group is U(1); in this simple case, there is only one gauge boson. In quantum chromodynamics, the more complicated group SU(3) has eight generators, corresponding to the eight gluons. The three W and Z bosons correspond (roughly) to the three generators of SU(2) in GWS theory.

Massive gauge bosons

For technical reasons involving gauge invariance, gauge bosons are described mathematically by field equations for massless particles. Therefore, at a naïve theoretical level all gauge bosons are required to be massless, and the forces that they describe are required to be long-ranged. The conflict between this idea and experimental evidence that the weak interaction has a very short range requires further theoretical insight.

According to the Standard Model, the W and Z bosons gain mass via the Higgs mechanism. In the Higgs mechanism, the four gauge bosons (of SU(2)×U(1) symmetry) of the unified electroweak interaction couple to a Higgs field. This field undergoes spontaneous symmetry breaking due to the shape of its interaction potential. As a result, the universe is permeated by a nonzero Higgs vacuum expectation value (VEV). This VEV couples to three of the electroweak gauge bosons (the Ws and Z), giving them mass; the remaining gauge boson remains massless (the photon). This theory also predicts the existence of a scalar Higgs boson, which may have been observed in experiments that were reported on 4 July 2012.^[2]

Beyond the Standard Model

Grand unification theories

A grand unified theory predicts additional gauge bosons named X and Y bosons. The hypothetical X and Y bosons direct interactions between quarks and leptons, hence violating conservation of baryon number and causing proton decay. Such bosons would be even more massive than W and Z bosons due to symmetry breaking. Analysis of data collected from such sources as the Super-Kamiokande neutrino detector has yielded no evidence of X and Y bosons.^{[來源請求]}

Gravitons

The fourth fundamental interaction, gravity, may also be carried by a boson, called the graviton. In the absence of experimental evidence and a mathematically coherent theory of quantum gravity, it is unknown whether this would be a gauge boson or not. The role of gauge invariance in general relativity is played by a similar symmetry: diffeomorphism invariance.