  Provided the measuring time is short enough, the full counting statistics
(FCS) of the charge pumped across a barrier as a result of a series of voltage
pulses are shown to be equivalent to the geometry of two planes. This
formulation leads to the FCS without the need for the usual non-equilibrium
(Keldysh) transport theory or the direct computation of the determinant of an
infinite-dimensional matrix. In the particular case of the application of N
Lorentzian pulses, we show the computation of the FCS reduces to the
diagonalization of an N x N matrix. We also use the formulation to compute the
core-hole response in the X-ray edge problem and the FCS for a square wave
pulse-train for the case of low transmission.
