在粒子物理学中，电弱交互作用是电磁作用与弱交互作用的统一描述，而这两种作用都是自然界中四种已知基本力。虽然在日常的低能量情况下，电磁作用与弱作用存在很大的差异，然而在超过统一温度，即数量级在100 GeV的情况下，这两种作用力会统合成单一的电弱作用力。因此如果宇宙是足够地热（约10K，在大爆炸发生不久以后温度才降至比上述低的水平），就只有一种电弱作用力，不会有分开的电磁作用与弱交互作用。

由于将基本粒子的电磁作用与弱作用统一的这项贡献，阿卜杜勒·萨拉姆、谢尔登·格拉肖以及史蒂文·温伯格获颁1979年的诺贝尔物理奖。电弱交互作用的理论目前经以下两个实验证明存在：

In particle physics, the electroweak interaction is the unified description of two of the four known fundamental interactions of nature: electromagnetism and the weak interaction. Although these two forces appear very different at everyday low energies, the theory models them as two different aspects of the same force. Above the unification energy, on the order of 100 GeV, they would merge into a single electroweak force. Thus, if the universe is hot enough (approximately 10 K, a temperature exceeded until shortly after the Big Bang), then the electromagnetic force and weak force merge into a combined electroweak force. During the electroweak epoch, the electroweak force separated from the strong force. During the quark epoch, the electroweak force split into the electromagnetic and weak force.