Nullfeld
Nullfeld is a term encountered in physics and mathematics to denote a field that vanishes identically on a given domain. The word is formed from the German words null (“zero”) and Feld (“field”), and in English-language texts it is often translated as “null field.” The term appears in specialized German-language literature on differential equations, electromagnetism, and gauge theories, where it serves to describe the trivial or vacuum solution of a field equation under certain boundary conditions.
Let F be a field defined on a domain Ω with values in a vector space V. F
In electromagnetism, for example, a region devoid of sources may admit the Nullfeld as a possible solution
Whether a solution is a Nullfeld can depend on boundary or initial data. Imposing nontrivial boundary conditions