![]() | This article may be too technical for most readers to understand.(June 2025) |
In high-energy physics, nonlinear electrodynamics (NED or NLED) refers to a family of generalizations of Maxwell electrodynamics which describe electromagnetic fields that exhibit nonlinear dynamics. [1] For a theory to describe the electromagnetic field (a U(1) gauge field), its action must be gauge invariant; in the case of , for the theory to not have Faddeev-Popov ghosts, this constraint dictates that the Lagrangian of a nonlinear electrodynamics must be a function of only (the Maxwell Lagrangian) and (where is the Levi-Civita tensor). [1] [2] [3] Notable NED models include the Born-Infeld model, [4] the Euler-Heisenberg Lagrangian, [5] and the CP-violating Chern-Simons theory . [2] [6] [7]
Some recent formulations also consider nonlocal extensions involving fractional U(1) holonomies on twistor space,[ citation needed ] though these remain speculative.