On Milstein-Type Methods for Free Stochastic Differential Equations

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Wibmer, Michael, Schlüchtermann, Georg
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866915895733911552
author Wibmer, Michael
Schlüchtermann, Georg
author_facet Wibmer, Michael
Schlüchtermann, Georg
contents Previously, the authors derived an analog of the Euler-Maru\-yama method (fEMM) for free stochastic differential equations (fSDEs) and proved strong convergence of order $γ=0.5$ in $L_1(φ)$-norm under certain assumptions. In this paper, we study the development of numerical methods for fSDEs which show strong convergence of order $γ=1$ in $L_\infty(φ)$. As a side effect, strong convergence of order $γ=0.5$ of fEMM can be extended to $L_p(φ)$ for $p\in[1,\infty]$. Utilizing the framework of multiple operator integrals (MOI) we derive a stochastic Itô-Taylor expansion of the solution of the fSDE. It is then possible to identify those free stochastic iterated integrals, which must be discretized in order to obtain strong convergence of order $γ=1$. The non-commutativity imposes additional difficulties showing that the iterated free stochastic integrals can be simulated directly only under special situations, different from the commutative case. We will show, which diffusion terms lead to a Milstein-type method of order $γ=1$. For the cases, where a direct calculation is not possible, we approximate the iterated integrals based on a subdivision of the discretization intervals. As for fEMM, all proposed methods obey strong convergence of order $γ=1$ in $L_p(φ),\, 1\leq p\leq \infty$. For all methods developed, we show that the numerical solution is uniformly bounded on finite time intervals.
format Preprint
id arxiv_https___arxiv_org_abs_2502_11233
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle On Milstein-Type Methods for Free Stochastic Differential Equations
Wibmer, Michael
Schlüchtermann, Georg
Probability
46L53, 46L54, 60H10, 65C30
Previously, the authors derived an analog of the Euler-Maru\-yama method (fEMM) for free stochastic differential equations (fSDEs) and proved strong convergence of order $γ=0.5$ in $L_1(φ)$-norm under certain assumptions. In this paper, we study the development of numerical methods for fSDEs which show strong convergence of order $γ=1$ in $L_\infty(φ)$. As a side effect, strong convergence of order $γ=0.5$ of fEMM can be extended to $L_p(φ)$ for $p\in[1,\infty]$. Utilizing the framework of multiple operator integrals (MOI) we derive a stochastic Itô-Taylor expansion of the solution of the fSDE. It is then possible to identify those free stochastic iterated integrals, which must be discretized in order to obtain strong convergence of order $γ=1$. The non-commutativity imposes additional difficulties showing that the iterated free stochastic integrals can be simulated directly only under special situations, different from the commutative case. We will show, which diffusion terms lead to a Milstein-type method of order $γ=1$. For the cases, where a direct calculation is not possible, we approximate the iterated integrals based on a subdivision of the discretization intervals. As for fEMM, all proposed methods obey strong convergence of order $γ=1$ in $L_p(φ),\, 1\leq p\leq \infty$. For all methods developed, we show that the numerical solution is uniformly bounded on finite time intervals.
title On Milstein-Type Methods for Free Stochastic Differential Equations
topic Probability
46L53, 46L54, 60H10, 65C30
url https://arxiv.org/abs/2502.11233