In mathematical physics, in particular electromagnetism, the Riemann–Silberstein vector, named after Bernhard Riemann and Ludwik Silberstein, (or sometimes ambiguously called the "electromagnetic field") is a complex vector that combines the electric field E and the magnetic field B.
Given an electric field E and a magnetic field B defined on a common region of spacetime, the Riemann–Silberstein vector is
where c is the speed of light, with some authors preferring to multiply the right hand side by an overall constant where ε0 is the permittivity of free space. It is analogous to the electromagnetic tensor F, a 2-vector used in the covariant formulation of classical electromagnetism.
In Silberstein's formulation, i was defined as the imaginary unit, and F was defined as a complexified 3-dimensional vector field. The value of F at an event was a bivector.