On the estimation of the Mori-Zwanzig memory integral

Abstract

We develop a thorough mathematical analysis to deduce conditions for the accuracy and convergence of different approximations of the memory integral in the Mori-Zwanzig (MZ) equation. In particular, we derive error bounds and sufficient convergence conditions for short-memory approximations, the t-model, and hierarchical (finite-memory) approximations. In addition, we derive useful upper bounds for the MZ memory integral, which allow us to estimate a priori the contribution of the MZ memory to the dynamics. Such upper bounds are easily computable for systems with finite-rank projections. Numerical examples are presented and discussed for linear and nonlinear dynamical systems evolving from random initial states.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 21, 2018
Source ID
10.1063/1.5003467

Entities

People

  • Daniele Venturi
  • Jason M. Dominy
  • Yuanran Zhu

Organizations

  • Air Force Office of Scientific Research
  • University of California

Tags

Fields of Study

  • Mathematics

Readers

  • Calculus or Mathematical Analysis
  • Fluid Dynamics.
  • Mathematical Modeling and Probability Theory.