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The weak nuclear force affects all leptons and quarks. It is the only force affecting neutrinos (except for gravitation, which is negligible on laboratory scales). The weak interaction enables all lepton and quark particles and antiparticles to interchange energy, mass, electric charge and flavor—effectively to change into each other.
Although the weak nuclear force used to be described by Fermi's theory of a contact four- fermion interaction, today we know that it is mediated by the W and Z bosons. Because of their large mass of about 90 GeV/c2, their mean life is limited by the uncertainty principleIn quantum physics, the Heisenberg uncertainty principle expresses a limitation on accuracy of (nearly) simultaneous measurement of observables such as the position and the momentum of a particle. It furthermore precisely quantifies the imprecision by pro to about 3 ×10−25 seconds. Even at the speed of light this effectively limits the range of the weak nuclear force to 10−18 meter, or about 1000 times smaller than the diameter of an atomic nucleusThe nucleus atomic nucleus is the center of an atom. It is composed of one or more protons and usually some neutrons as well. The number of protons in an atom's nucleus is called the atomic number, and determines which element the atom is (for example hyd.
The laws of natureA physical law or a law of nature is a scientific generalization based on empirical observations. Laws of nature are conclusions drawn from, or hypotheses confirmed by, scientific experiments. The production of a summary description of nature in the form were long thought to remain the same under mirror reflection. The results of an experiment viewed via a mirror were expected to be identical to the results of a mirror-reflected copy of the experimental apparatus. This is called the law of parityParity is a concept of equality of status or functional equivalence. It has several different specific definitions. Parity in quantum mechanics Particles have a quantum mechanical property of parity . According to quantum mechanics, the conservation of th conservation in physicists' jargon. However, in the mid-1950's Chen Ning YangChen Ning Franklin Yang ( pinyin: Yang Zhenning) (born September 22, 1922) is a Chinese American physicist, who worked on statistical mechanics and symmetry principles. He received the Nobel Prize in Physics in 1957 at the age of 35, with Tsung-Dao Lee, f and Tsung-Dao LeeTsung-Dao Lee ( Pinyin: L Zhengdao) (born November 24, 1926) is a Chinese American physicist who, for his work on the parity laws, with Chen Ning Yang, experimentally verified by Chien-Shiung Wu, received the Nobel Prize in Physics. Lee and Yang were the suggested that the weak interaction might violate this law. Chien Shiung Wu and collaborators confirmed this prediction in 1957, earning Yang and Lee the 1957 Nobel prize in physics.
The Standard ModelThe Standard Model of particle physics is a theory which describes the strong, weak, and electromagnetic fundamental forces, as well as the fundamental particles that make up all matter. It is a quantum field theory, and consistent with both quantum mecha of particle physics describes the electromagnetic force and the weak nuclear force as two different aspects of a single electroweak force, the theory of which was developed around 1968 by Sheldon Glashow, Abdus Salam and Steven Weinberg (more at W and Z bosons). They were awarded the 1979 Nobel prize in physics for their work.