Vacuum solution

A vacuum box, a solution is the solution equation for the case that the field -generating source is the same everywhere zero, except at a single point. This is known as a point charge. Mathematically, an analytical model with the Dirac delta function such fields.

Electromagnetism

In the case of the Maxwell's equations of electromagnetism vacuum solution represents the electromagnetic field in a spatial region where there is no electric charge (), and no currents () or in the form of co-variant:

Relativity theory

Another example is Einstein's general theory of relativity. In this case, a vacuum solution represents the gravitational field in a region of spacetime in which (up to a single point ) is no mass, ie for the energy -momentum tensor is valid everywhere ( to a point ):

The most significant vacuum solutions of ART are the Schwarzschild metric and the Kerr metric.

• Electrodynamics
• General Theory of Relativity