Search results
Results from the WOW.Com Content Network
Fermi first introduced this coupling in his description of beta decay in 1933. [3] The Fermi interaction was the precursor to the theory for the weak interaction where the interaction between the proton–neutron and electron–antineutrino is mediated by a virtual W − boson, of which the Fermi theory is the low-energy effective field theory.
The Fermi contact interaction is the magnetic interaction between an electron and an atomic nucleus. Its major manifestation is in electron paramagnetic resonance and nuclear magnetic resonance spectroscopies, where it is responsible for the appearance of isotropic hyperfine coupling. This requires that the electron occupy an s-orbital.
Fermi's golden rule. In quantum physics, Fermi's golden rule is a formula that describes the transition rate (the probability of a transition per unit time) from one energy eigenstate of a quantum system to a group of energy eigenstates in a continuum, as a result of a weak perturbation. This transition rate is effectively independent of time ...
Enrico Fermi. Enrico Fermi ForMemRS (Italian: [enˈriːko ˈfermi]; 29 September 1901 – 28 November 1954) was an Italian and naturalized American physicist, renowned for being the creator of the world's first artificial nuclear reactor, the Chicago Pile-1, and a member of the Manhattan Project. He has been called the "architect of the nuclear ...
e. Fermi liquid theory (also known as Landau's Fermi-liquid theory) is a theoretical model of interacting fermions that describes the normal state of the conduction electrons in most metals at sufficiently low temperatures. [1] The theory describes the behavior of many-body systems of particles in which the interactions between particles may be ...
Fermi's theory of the weak interaction. The interaction term has a V − A (vector minus axial) form. The Gross–Neveu model. This is a four-fermi theory of Dirac fermions without chiral symmetry and as such, it may or may not be massive. The Thirring model. This is a four-fermi theory of fermions with a vector coupling. The Nambu–Jona ...
Although the weak interaction was once described by Fermi's theory, the discovery of parity violation and renormalization theory suggested that a new approach was needed. In 1957, Robert Marshak and George Sudarshan and, somewhat later, Richard Feynman and Murray Gell-Mann proposed a V − A ( vector minus axial vector or left-handed ...
Fermi's interaction showing the 4-point fermion vector current, coupled under the Fermi coupling constant, G F. Fermi's theory was the first theoretical effort in describing nuclear decay rates for beta decay. The Gamow–Teller theory was a necessary extension of Fermi's theory.