Enfermion

Enfermion is a term that appears in speculative physics discussions and science fiction to denote a hypothetical fermionic particle. It is not part of the established Standard Model, and there is no experimental evidence for its existence. In generic usage, an enfermion is assumed to be a fermion with half-integer spin, obeying the Pauli exclusion principle, and it may be Dirac or Majorana in nature depending on the model.

In theoretical proposals, enfermions are typically assigned a set of quantum numbers under hypothetical gauge groups and may interact with Standard Model particles through heavy mediators or portal couplings. Their properties—such as mass, charge, and interaction strengths—are model dependent and not fixed by a single framework.

Potential roles proposed for enfermions include serving as dark matter candidates, contributing to neutrino mass generation, or acting as components of hidden or composite sectors. In some scenarios, enfermions are envisioned as sterile-like fermions that mix weakly with known fermions or as part of extended families beyond the Standard Model.

Experimental status is currently inconclusive; searches for new fermions at colliders, in precision measurements, and through astrophysical or direct detection methods constrain possible masses and couplings, but no confirmed signal has been found. The term remains informal and is primarily used in speculative writing rather than as a widely adopted scientific designation. See also: fermion, Dirac fermion, Majorana fermion, sterile neutrino, dark matter.