Have a personal or library account? Click to login
A Fourier Analysis Based New Look at Integration Cover

A Fourier Analysis Based New Look at Integration

Open Access
|Jul 2023

Abstract

We approach the problem of integration for rough integrands and integrators, typically representing trajectories of stochastic processes possessing only some Hölder regularity of possibly low order, in the framework of para-control calculus. For this purpose, we first decompose integrand and integrator into Paley–Littlewood packages along the Haar–Schauder system. By careful estimation of the components of products of packages of the integrand and derivatives of the integrator we obtain a characterization of Young’s integral. For the most interesting case of functions with Hölder regularities that sum up to an order below 1 we have to employ the concept of para-control of integrand and integrator with respect to a reference function for which a version of antisymmetric Lévy area is known to exist. This way we obtain an interpretation of the rough path integral. Lévy areas being known for most frequently used stochastic processes such as (fractional) Brownian motion, this integral serves as a basis for pathwise stochastic calculus, as the integral in classical rough path analysis.

DOI: https://doi.org/10.2478/amsil-2023-0011 | Journal eISSN: 2391-4238 | Journal ISSN: 0860-2107
Language: English
Page range: 149 - 168
Submitted on: Mar 29, 2023
Accepted on: Jul 10, 2023
Published on: Jul 26, 2023
Published by: University of Silesia in Katowice, Institute of Mathematics
In partnership with: Paradigm Publishing Services
Publication frequency: 2 issues per year

© 2023 Peter Imkeller, Nicolas Perkowski, published by University of Silesia in Katowice, Institute of Mathematics
This work is licensed under the Creative Commons Attribution 4.0 License.