Section
|
Mathematics
|
Title
|
On the spectral set of a linear discrete system with stable Lyapunov exponents
|
Author(-s)
|
Banshchikova I.N.ab,
Popova S.N.bc
|
Affiliations
|
Izhevsk State Agricultural Academya,
Udmurt State Universityb,
Institute of Mathematics and Mechanics, Ural Branch of the Russian Academy of Sciencesc
|
Abstract
|
Let us fix a certain class of perturbations of the coefficient matrix $A(\cdot)$ for a discrete time-varying linear system
$$x(m+1)=A(m)x(m),\quad m\in\mathbb Z,\quad x\in\mathbb R^n,$$
where $A(\cdot)$ is completely bounded on $\mathbb Z$, i.e., $\sup_{m\in\mathbb Z}\bigl(\|A(m)\|+\|A^{-1}(m)\|\bigr)<\infty$. The spectral set of this system, corresponding to a given class of perturbations, is a collection of all Lyapunov spectra (with multiplicities) for perturbed systems, when the perturbations range over this class all. The main attention is paid to the class ${\cal R}$ of perturbed systems
$$y(m+1)=A(m)R(m)y(m),\quad m\in\mathbb Z,\quad y\in\mathbb R^n,$$
where $R(\cdot)$ is completely bounded on $\mathbb Z$, as well as its subclasses ${\cal R}_{\delta}$, where $\sup_{m\in\mathbb Z}\|R(m)-E\|<\delta$, $\delta>0$. For an original system with stable Lyapunov exponents, we prove that the spectral set $\lambda({\cal R})$ of class ${\cal R}$ coincides with the set of all ordered ascending sets of $n$ numbers. Moreover, for any $\Delta> 0$ there exists an $\ell =\ell(\Delta)> 0 $ such that for any $\delta<\Delta$ the spectral set $\lambda({\cal R}_{\ell\delta})$ contains the $\delta$-neighborhood of the Lyapunov spectrum of the unperturbed system.
|
Keywords
|
discrete time-varying linear system, Lyapunov exponents, perturbations of coefficients
|
UDC
|
517.929.2
|
MSC
|
39A06, 39A30
|
DOI
|
10.20537/vm160102
|
Received
|
1 February 2016
|
Language
|
Russian
|
Citation
|
Banshchikova I.N., Popova S.N. On the spectral set of a linear discrete system with stable Lyapunov exponents, Vestnik Udmurtskogo Universiteta. Matematika. Mekhanika. Komp'yuternye Nauki, 2016, vol. 26, issue 1, pp. 15-26.
|
References
|
- Demidovich V.B. On a criterion of stability for difference equations, Differ. Uravn., 1969, vol. 5, no. 7, pp. 1247-1255 (in Russian).
- Gaishun I.V. Sistemy s diskretnym vremenem (Discrete-time systems), Minsk: Institute of Mathematics of the National Academy of Sciences of Belarus, 2001, 400 p.
- Izobov N.A. Linear systems of ordinary differential equations, Journal of Soviet Mathematics, 1976, vol. 5, issue 1, pp. 46-96.
- Vinograd R.E. On the central characteristic exponent of a system of differential equations, Mat. Sb. (N. S.), 1957, vol. 42, no. 2, pp. 207-222 (in Russian).
- Millionshchikov V.M. Proof of attainability of central exponents of linear systems, Sib. Mat. Zh., 1969, vol. 10, no. 1, pp. 99-104 (in Russian).
- Millionshchikov V.M. Robust properties of linear systems of differential equations, Differ. Uravn., 1969, vol. 5, no. 10, pp. 1775-1784 (in Russian).
- Bylov B.F., Izobov N.A. Necessary and sufficient conditions for stability of characteristic exponents of linear system, Differ. Uravn., 1969, vol. 5, no. 10, pp. 1794-1803 (in Russian).
- Bylov B.F., Vinograd R.E., Grobman D.M., Nemytskii V.V. Teoriya pokazatelei Lyapunova (Theory of Lyapunov exponents), Moscow: Nauka, 1966, 576 p.
|
Full text
|
|