What is the weak interaction and how does it relate to particle decay?

The weak interaction is a fundamental force that governs the decay of subatomic particles.

The weak interaction is one of the four fundamental forces of nature, alongside gravity, electromagnetism, and the strong interaction. It is responsible for the decay of subatomic particles, such as beta decay, where a neutron decays into a proton, an electron, and an antineutrino. The weak interaction is mediated by the exchange of W and Z bosons, which are very massive particles that can only exist for a very short time.

The weak interaction is weak compared to the other fundamental forces, which is why it is called the weak interaction. It has a very short range, only acting over distances of the order of 10^-18 meters. However, it is responsible for some of the most important processes in the universe, such as the fusion of hydrogen into helium in stars, which powers the sun and other stars.

The weak interaction is also responsible for the phenomenon of parity violation, which was first observed in the decay of cobalt-60 nuclei. This led to the discovery of the weak interaction and the development of the electroweak theory, which unifies the weak interaction with the electromagnetic force. The electroweak theory is an important part of the Standard Model of particle physics, which describes the behavior of subatomic particles and the fundamental forces that govern their behavior.