A comparison principle based on couplings of partial integro-differential operators

Journal Article (2026)
Author(s)

Serena Della Corte (TU Delft - Applied Probability)

Fabian Fuchs (LUISS Guido Carli University, Bielefeld University)

Richard C. Kraaij (TU Delft - Applied Probability)

Max Nendel (University of Waterloo)

Research Group
Applied Probability
DOI related publication
https://doi.org/10.1016/j.matpur.2026.103872
More Info
expand_more
Publication Year
2026
Language
English
Research Group
Applied Probability
Volume number
210
Reuse Rights

Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.

Abstract

This paper is concerned with a comparison principle for viscosity solutions to Hamilton–Jacobi (HJ), –Bellman (HJB), and –Isaacs (HJI) equations for general classes of partial integro-differential operators. Our approach contributes to the literature in three ways: (1) We cast the Crandall–Ishii Lemma into a test function framework to tackle a wide class of second-order integro-differential operators in the spirit of the classical doubling of variables method. (2) We provide a unified approach to estimate the difference of Hamiltonians by adapting the probabilistic notion of couplings to an analytic setting. (3) We strengthen the sup-norm contractivity resulting from the comparison principle to one that encodes continuity in the strict topology. We apply our theory to a variety of examples, in particular, to second-order differential operators and, more generally, generators of spatially inhomogeneous Lévy processes.