  We study the propogation and diffusion of electric charge fluctuations in
high energy heavy ion collisions using the Cattaneo form for the dissipative
part of the electric current. As opposed to the ordinary diffusion equation
this form limits the speed at which charge can propagate. Including the noise
term in the current, which arises uniquely from the fluctuation-dissipation
theorem, we calculate the balance functions for charged hadrons in a simple 1+1
dimensional Bjorken hydrodynamical model. Limiting the speed of propagation of
charge fluctuations increases the height and reduces the width of these balance
functions when plotted versus rapidity. We also estimate the numerical value of
the associated diffusion time constant from AdS/CFT theory.
