Invariant cones for jump-diffusions in infinite dimensions
Stefan Tappe
TL;DR
The paper develops robust invariance criteria for closed convex cones in infinite-dimensional SPDEs with jump-diffusion, relaxing the previous requirement that cones be generated by an unconditional Schauder basis to an approximate-generation notion, and providing a simplified drift condition. It proves diffusion and general jump-diffusion invariance theorems, with additional results on isomorphic and product-cone transformations, and extends these results to both standard and abstract $L^2$-spaces. The framework encompasses self-dual and $L^2$-type cones, and the authors illustrate the theory across a broad set of applications in natural sciences and economics, including HJMM forward-rate dynamics, stochastic cable/heat equations, and energy/credit markets. Collectively, these results offer practical, mathematically rigorous tools to enforce positivity and monotonicity constraints in high-dimensional SPDE models with jumps. The work thereby enhances the reliability and scope of positivity-preserving modeling in infinite-dimensional stochastic systems.
Abstract
In this paper we provide sufficient conditions for stochastic invariance of closed convex cones for stochastic partial differential equations (SPDEs) of jump-diffusion type, and clarify when these conditions are necessary. Our results apply to the positive cone of abstract $L^2$-spaces. Furthermore, we present a series of applications, where we investigate SPDEs arising in natural sciences and economics.
