Weak Nuclear Force

The Weak Nuclear Force

The weak nuclear force, first discovered by Fermi in 1933 and is during that time called Fermi interaction, is observed to be responsible for the radioactive decays of particles into smaller pieces of matter, e.g. beta decays, of many nuclei. In beta decays, unstable nuclei change from one type to another by emitting an electron or an antineutrino. Radioactive decays are usually created in high-speed particle accelerators. By observing the neutrinos, physicists are able to study the weak force. The weak nuclear force cannot hold the nucleus of the atom together, since its range is only about 1/100 of the size of an atomic nucleus. Its range of interaction is even shorter than that of the strong interaction, and is 10 trillion times less powerful. But it has influence in the interactions of leptons (Klauskopf and Beiser, 1991:252; Capra, 1975:215). Because of this, it is much weaker than the electromagnetic and the strong nuclear force, although it is much stronger than gravity. The weak nuclear force is so weak that they cannot hold anything together at all. But it mediates the conversion of certain particles into other particles, e.g. when protons join each other to form helium nuclei, the process called nuclear fusion. Weak interactions are presumably produced by the exchange of a very heavy particle, called the “W meson.” John Lederer presents in a table below a summary of the elementary particles and the forces guiding their interactions (see also Physicist Sheldon Glasgow, 1991:97, Table 2).

In terms of their interaction, all particles and their anti-particles can be grouped into two broad categories: leptons and hadrons. Hadrons are strongly interacting particles which are further subdivided into mesons and baryons. The electromagnetic interactions (electromagnetism) hold together the atoms and molecules, while the strong interactions (strong nuclear force) bind the atomic nuclei (protons and neutrons) together. The weak interactions do not bind anything together at all, but, having extremely short range, involve the leptons.

In terms of their interaction, all particles and their anti-particles can be grouped into two broad categories: leptons and hadrons. Hadrons are strongly interacting particles which are further subdivided into mesons and baryons. The electromagnetic interactions (electromagnetism) hold together the atoms and molecules, while the strong interactions (strong nuclear force) bind the atomic nuclei (protons and neutrons) together. The weak interactions do not bind anything together at all, but, having extremely short range, involve the leptons.