In vector calculus, a Laplacian vector field is a vector field which is both irrotational and incompressible. If the field is denoted as v, then it is described by the following differential equations:
A Laplacian vector field in the plane satisfies the Cauchy-Riemann equations: it is holomorphic.
Since the curl of v is zero, it follows that v can be expressed as the gradient of a scalar potential (see irrotational field) φ :
Then, since the divergence of v is also zero, it follows from equation (1) that
which is equivalent to
Therefore, the potential of a Laplacian field satisfies Laplace's equation.