Well-posedness of the stochastic thin-film equation with an interface potential
Antonio Agresti, Max Sauerbrey
TL;DR
This work establishes a rigorous local well-posedness theory for stochastic thin-film-type equations with degenerate fourth-order operators on the torus, using stochastic maximal $L^p$-regularity and a carefully regularized framework. It proves local existence and blow-up criteria in any dimension, and develops instantaneous regularization that enables parameter-independent blow-up control. In one dimension, the authors derive $\boldsymbol{\alpha}$-entropy and energy estimates to obtain global well-posedness for a broad mobility class including $m(u)=u^n$ with $n<6$ under repulsive interface potentials, and treat both Itô and Stratonovich noises. The approach hinges on transferring regularized results to the original equation, preserving positivity, and providing sharp a priori bounds that close global-in-time behavior in 1D. These results advance understanding of stochastic degenerate parabolic PDEs arising in thin-film dynamics and offer a solid foundation for numerical schemes and further analysis of contact-line and interface phenomena.
Abstract
We consider strictly positive solutions to a class of fourth-order conservative quasilinear SPDEs on the $d$-dimensional torus modeled after the stochastic thin-film equation. We prove local Lipschitz estimates in Bessel potential spaces under minimal assumptions on the parameters and corresponding stochastic maximal $L^p$-regularity estimates for thin-film type operators with measurable in-time coefficients. As a result, we deduce local well-posedness of the stochastic thin-film equation as well as blow-up criteria and instantaneous regularization for the solution. In dimension one, we additionally close $α$-entropy estimates and subsequently an energy estimate for the stochastic thin-film equation with an interface potential so that global well-posedness follows. We allow for a wide range of mobility functions including the power laws $u^n$ for $n\in [0,6)$ as long as the interface potential is sufficiently repulsive.
