Category: Fermions

Heavy fermion material
In solid-state physics, heavy fermion materials are a specific type of intermetallic compound, containing elements with 4f or 5f electrons in unfilled electron bands. Electrons are one type of fermion
Nielsen–Ninomiya theorem
In lattice field theory, the Nielsen–Ninomiya theorem is a no-go theorem about placing chiral fermions on the lattice. In particular, under very general assumptions such as locality, hermiticity, and
The axino is a hypothetical elementary particle predicted by some theories of particle physics. Peccei–Quinn theory attempts to explain the observed phenomenon known as the strong CP problem by introd
In supergravity theories combining general relativity and supersymmetry, the gravitino (G͂) is the supersymmetric partner of the hypothesized graviton. It has been suggested as a candidate for dark ma
Dirac fermion
In physics, a Dirac fermion is a spin-½ particle (a fermion) which is different from its antiparticle. The vast majority of fermions – perhaps all – fall under this category.
Fermion doubling
In lattice field theory, fermion doubling occurs when naively putting fermionic fields on a lattice, resulting in more fermionic states than expected. For the naively discretized Dirac fermions in Euc
Hastatic order
Hastatic order is a fundamental way of breaking double "time-reversal" symmetry. It is present in the heavy-fermion compound URu2Si2. This order was dubbed hastatic from hasta, the Latin word for "spe
Kadowaki–Woods ratio
The Kadowaki–Woods ratio is the ratio of A, the quadratic term of the resistivity and γ2, the linear term of the specific heat. This ratio is found to be a constant for transition metals, and for heav
Luttinger–Ward functional
In solid state physics, the Luttinger–Ward functional, proposed by Joaquin Mazdak Luttinger and John Clive Ward in 1960, is a scalar functional of the bare electron-electron interaction and the renorm
In supersymmetry, a gluino (symbol g͂) is the hypothetical supersymmetric partner of a gluon. In supersymmetric theories, gluinos are Majorana fermions and interact via the strong force as a color oct
Majorana fermion
A Majorana fermion (/maɪəˈrɑːnə ˈfɛərmiːɒn/), also referred to as a Majorana particle, is a fermion that is its own antiparticle. They were hypothesised by Ettore Majorana in 1937. The term is sometim
Foldy–Wouthuysen transformation
The Foldy–Wouthuysen transformation was historically significant and was formulated by Leslie Lawrance Foldy and Siegfried Adolf Wouthuysen in 1949 to understand the nonrelativistic limit of the Dirac
Dirac equation
In particle physics, the Dirac equation is a relativistic wave equation derived by British physicist Paul Dirac in 1928. In its free form, or including electromagnetic interactions, it describes all s
Luttinger's theorem
In condensed matter physics, Luttinger's theorem is a result derived by J. M. Luttinger and J. C. Ward in 1960 that has broad implications in the field of electron transport. It arises frequently in t
Dirac equation in curved spacetime
In mathematical physics, the Dirac equation in curved spacetime is a generalization of the Dirac equation from flat spacetime (Minkowski space) to curved spacetime, a general Lorentzian manifold.
Pomeranchuk instability
The Pomeranchuk instability is an instability in the shape of the Fermi surface of a material with interacting fermions, causing Landau’s Fermi liquid theory to break down. It occurs when a Landau par
In particle physics, a fermion is a particle that follows Fermi–Dirac statistics. Generally, it has a half-odd-integer spin: spin 1/2, spin 3/2, etc. In addition, these particles obey the Pauli exclus
Fermi liquid theory
Fermi liquid theory (also known as Landau's Fermi-liquid theory) is a theoretical model of interacting fermions that describes the normal state of most metals at sufficiently low temperatures. The int
Staggered fermion
In lattice field theory, staggered fermions (also known as Kogut–Susskind fermions) are a fermion discretization that reduces the number of fermion doublers from sixteen to four. They are one of the f
Rarita–Schwinger equation
In theoretical physics, the Rarita–Schwinger equation is therelativistic field equation of spin-3/2 fermions. It is similar to the Dirac equation for spin-1/2 fermions. This equation was first introdu
In supersymmetry, the neutralino is a hypothetical particle. In the Minimal Supersymmetric Standard Model (MSSM), a popular model of realization of supersymmetry at a low energy, there are four neutra
In particle physics, for models with N=1 supersymmetry a higgsino, symbol H͂, is the superpartner of the Higgs field. A higgsino is a Dirac fermionic field with spin 1⁄2 and it refers to a weak isodou