$L^p$-Boltzmann-Gibbs principle via Littlewood-Paley-Stein inequality
Tadahisa Funaki
TL;DR
The paper develops an L^p Boltzmann-Gibbs principle for a one-dimensional asymmetric Ginzburg-Landau interface model by leveraging the Littlewood-Paley-Stein inequality. It provides second- and first-order replacement estimates with explicit, uniform-in-size error bounds, applicable to both strong and weak asymmetry regimes, under convexity assumptions on the potential. The methodology fuses Itô-Tanaka (Kipnis-Varadhan) arguments, a localized Sobolev-type LP-Stein framework, an L^p variational formula, and an L^p equivalence of ensembles to control fluctuations at multiple scales. These results contribute to a robust, high-integrability understanding of equilibrium fluctuations and are pertinent to KPZ-type weak universality analyses.
Abstract
In this paper, we establish the Boltzmann-Gibbs principle in the $L^p$ sense by applying the Littlewood-Paley-Stein inequality. Our model is an asymmetric Ginzburg-Landau interface model on a one-dimensional periodic lattice. Assuming convexity of the potential,we derive detailed error estimates, particularly their dependence on the size of the system and the size of the region on which the sample average is taken. Notably, the estimates are uniform in the strength of the asymmetry.
