  In disordered metals, electron-electron interactions are the origin of a
small correction to the conductivity, the "Altshuler-Aronov correction". Here
we investigate the Altshuler-Aronov correction of a conductor in which the
electron motion is ballistic and chaotic. We consider the case of a double
quantum dot, which is the simplest example of a ballistic conductor in which
the Altshuler-Aronov correction is nonzero. The fact that the electron motion
is ballistic leads to an exponential suppression of the correction if the
Ehrenfest time is larger than the mean dwell time or the inverse temperature.
