Dirac field

In physics, a Dirac field is a fermionic field (usually a quantized field, as usual in quantum field theory) associated with spin 1/2 fermions such as the electron or muon.

The Dirac field transforms as the unconstrained spinor, and it satisfies the Dirac equation. The usual free Lagrangian for the Dirac field is

<math>{\mathcal L} = \bar\Psi (i\partial_\mu \gamma^\mu - m)\Psi</math>

The Dirac fields are important components of Quantum electrodynamics and the Standard model.

A Dirac field is equivalent to two Majorana fields with the same mass.

A massless Dirac field is equivalent to two (massless) Weyl fields.