D'Alembert Operator - Green's Function

Green's Function

The Green's function for the d'Alembertian is defined by the equation

where is the Dirac delta function and and are two points in Minkowski space.

A special solution is given by the retarded Green's function which corresponds to signal propagation only forward in time

where is the Heaviside step function.

Read more about this topic:  D'Alembert Operator

Famous quotes containing the words green and/or function:

    Sea waves are green and wet,
    But up from where they die
    Rise others vaster yet,
    And those are brown and dry.
    Robert Frost (1874–1963)

    Any translation which intends to perform a transmitting function cannot transmit anything but information—hence, something inessential. This is the hallmark of bad translations.
    Walter Benjamin (1892–1940)