weak nuclear force

The weak interaction (often called the weak force or sometimes the weak nuclear force) is one of the four fundamental interactions of nature. In the Standard Model of particle physics, it is due to the exchange of the heavy W and Z bosons. Its most familiar effect is beta decay (of neutrons in atomic nuclei) and the associated radioactivity. The word "weak" derives from the fact that the field strength is some 1013 times less than that of the strong force.
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The force of nature through which interactions involving neutrinos take place. This force is much weaker than the strong nuclear force. It has been proven to be linked to the electromagnetic force at high energies to create a new force known as the electroweak force.