Deep neural network approximation for high-dimensional parabolic partial integro-differential equations
Marcin Baranek
TL;DR
The paper proves the existence of a ReLU neural network that can approximate the solution to a high-dimensional parabolic integro-differential equation with a Lévy-integral term, by leveraging the Feynman-Kac representation that expresses the solution as expectations of path functionals of an SDE with jumps. It develops a discretization-based construction of the stochastic dynamics using Euler-type schemes with Poisson-jump structure, and then shows how the two fundamental expectations—$\mathbb{E}[g(X_T^{(t,x)})]$ and $\mathbb{E}[\int_t^T b(s,X_s^{(t,x)}) ds]$—can be approximated by Monte Carlo estimators represented as DNNs. The main theoretical result (Theorem th:main_theorem) provides an existence claim for a ReLU network $\phi$ that achieves $L^2$ error at most $\delta$ with explicit dimension- and error-dependent size bounds, under growth and regularity assumptions encoded in classes $\mathcal{B}$, $\mathcal{G}$, and $\mathcal{C}$. The work is purely theoretical, establishing a constructive framework to bypass the curse of dimensionality in high-dimensional integro-differential equations, though no numerical experiments are provided.
Abstract
In this article, we investigate the existence of a deep neural network (DNN) capable of approximating solutions to partial integro-differential equations while circumventing the curse of dimensionality. Using the Feynman-Kac theorem, we express the solution in terms of stochastic differential equations (SDEs). Based on several properties of classical estimators, we establish the existence of a DNN that satisfies the necessary assumptions. The results are theoretical and don't have any numerical experiments yet.
