Comment on: `Pipe Network Model for Scaling of Dynamic Interfaces in Porous Media'

Abstract

We argue that a proposed exponent identity [Phys. Rev. Lett 85, 1238 (2000)] for interface roughening in spontaneous imbibition is wrong. It rests on the assumption that the fluctuations are controlled by a single time scale, but liquid conservation imposes two distinct time scales.

1 page, to appear in Phys. Rev. Lett