A function 
such that
The most common use of a vector potential is the representation of a magnetic field. If a vector field has zero divergence, it may be represented by a vector potential.
See also
Divergence, Helmholtz's Theorem, Potential Function, Solenoidal Field, Vector Field
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Cite this as:
Weisstein, Eric W. "Vector Potential." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/VectorPotential.html