Jacobi Stability Analysis for Systems of ODEs Using Symbolic Computation
Bo Huang, Dongming Wang, Jing Yang
TL;DR
This paper introduces algorithmic, symbolic methods to analyze Jacobi stability within the Kosambi–Cartan–Chern (KCC) framework for general first-order ODE systems $\dot{\boldsymbol{x}}=\boldsymbol{f}(\boldsymbol{x},\boldsymbol{\mu})$. It presents two schemes: a QE-based approach (Jacobi Test I) to decide the existence of Jacobi-stable fixed points, and a semi-algebraic approach (Jacobi Test II) to determine parameter regions yielding a prescribed number of Jacobi-stable fixed points. Theoretical results connect Jacobi stability to the spectrum of $J^2$, with practical reductions to algebraic conditions and real solution classifications, enabling application to models such as the Brusselator, Cdc2-Cyclin B/Wee1, and Lorenz–Stenflo. Experiments demonstrate the feasibility and limitations of the methods, highlighting that the symbolic approach is most tractable for small to moderate systems and may benefit from model reduction for larger ones. Overall, the work provides a principled, algorithmic pathway to quantify Jacobi stability in nonlinear dynamical systems.
Abstract
The classical theory of Kosambi-Cartan-Chern (KCC) developed in differential geometry provides a powerful method for analyzing the behaviors of dynamical systems. In the KCC theory, the properties of a dynamical system are described in terms of five geometrical invariants, of which the second corresponds to the so-called Jacobi stability of the system. Different from that of the Lyapunov stability that has been studied extensively in the literature, the analysis of the Jacobi stability has been investigated more recently using geometrical concepts and tools. It turns out that the existing work on the Jacobi stability analysis remains theoretical and the problem of algorithmic and symbolic treatment of Jacobi stability analysis has yet to be addressed. In this paper, we initiate our study on the problem for a class of ODE systems of arbitrary dimension and propose two algorithmic schemes using symbolic computation to check whether a nonlinear dynamical system may exhibit Jacobi stability. The first scheme, based on the construction of the complex root structure of a characteristic polynomial and on the method of quantifier elimination, is capable of detecting the existence of the Jacobi stability of the given dynamical system. The second algorithmic scheme exploits the method of semi-algebraic system solving and allows one to determine conditions on the parameters for a given dynamical system to have a prescribed number of Jacobi stable fixed points. Several examples are presented to demonstrate the effectiveness of the proposed algorithmic schemes.
