The stochastic porous medium equation in one dimension
Abstract
We study the porous medium equation (PME) in one space dimension in presence of additive non-conservative white noise, and interpreted as a stochastic growth equation for the height field of an interface. We predict the values of the two growth exponents and using the functional RG. Extensive numerical simulations show agreement with the predicted values for these exponents, however they also show anomalous scaling with an additional "local" exponent , as well as multiscaling originating from broad distributions of local height differences. The stationary measure of the stochastic PME is found to be well described by a random walk model, related to a Bessel process. This model allows for several predictions about the multiscaling properties.
Cite
@article{arxiv.2501.10975,
title = {The stochastic porous medium equation in one dimension},
author = {Maximilien Bernard and Andrei A. Fedorenko and Pierre Le Doussal and Alberto Rosso},
journal= {arXiv preprint arXiv:2501.10975},
year = {2026}
}