The Fundamental Solution to Laplace’s Equation
Consider the fundamental solution to the Laplace operator:
in 3D
and
in 2D
where the variables x and y represent coordinate positions in space x = (x1, x2, x3) and y = (y1, y2, y3).
The fundamental solution has the property
in Ω
where the derivatives are taken with respect to x and δ is the Dirac delta distribution.
The Dirac delta has the property that when used in an integral it samples the value of a function f at y: