Skip to main content

1989 | Buch

Practical Numerical Algorithms for Chaotic Systems

verfasst von: Thomas S. Parker, Leon O. Chua

Verlag: Springer New York

insite
SUCHEN

Über dieses Buch

One of the basic tenets of science is that deterministic systems are completely predictable-given the initial condition and the equations describing a system, the behavior of the system can be predicted 1 for all time. The discovery of chaotic systems has eliminated this viewpoint. Simply put, a chaotic system is a deterministic system that exhibits random behavior. Though identified as a robust phenomenon only twenty years ago, chaos has almost certainly been encountered by scientists and engi­ neers many times during the last century only to be dismissed as physical noise. Chaos is such a wide-spread phenomenon that it has now been reported in virtually every scientific discipline: astronomy, biology, biophysics, chemistry, engineering, geology, mathematics, medicine, meteorology, plasmas, physics, and even the social sci­ ences. It is no coincidence that during the same two decades in which chaos has grown into an independent field of research, computers have permeated society. It is, in fact, the wide availability of inex­ pensive computing power that has spurred much of the research in chaotic dynamics. The reason is simple: the computer can calculate a solution of a nonlinear system. This is no small feat. Unlike lin­ ear systems, where closed-form solutions can be written in terms of the system's eigenvalues and eigenvectors, few nonlinear systems and virtually no chaotic systems possess closed-form solutions.

Inhaltsverzeichnis

Frontmatter
Chapter 1. Steady-State Solutions and Limit Sets
Abstract
In this section, we define dynamical systems and present some useful facts from the theory of differential equations.
Thomas S. Parker, Leon O. Chua
Chapter 2. Poincaré Maps
Abstract
A classical technique for analyzing dynamical systems is due to Poincaré. It replaces the flow of an nth-order continuous-time system with an (n − 1)th-order discrete-time system called the Poincaré map. The definition of the Poincaré map ensures that its limit sets correspond to limit sets of the underlying flow. The Poincaré map’s usefulness lies in the reduction of order and the fact that it bridges the gap between continuous- and discrete-time systems.
Thomas S. Parker, Leon O. Chua
Chapter 3. Stability of Limit Sets
Abstract
Stable limit sets are of supreme importance in experimental and numerical settings because they are the only kind of limit set that can be observed naturally, that is, by simply letting the system run. In this chapter, we examine the conditions for a limit set to be stable.
Thomas S. Parker, Leon O. Chua
Chapter 4. Integration of Trajectories
Abstract
The most important numerical task in the simulation of continuous-time dynamical systems is the calculation of trajectories.
It is quite common for researchers to treat an integration routine as a black box—given the initial condition, the final time, and the error tolerance, out pops the final state. There is nothing wrong with this approach; indeed, the user should be insulated from the internal details of the coding of an integration routine.
Thomas S. Parker, Leon O. Chua
Chapter 5. Locating Limit Sets
Abstract
The first step in analyzing a dynamical system is to determine the location and stability type of its limit sets. In this chapter, we present algorithms that locate equilibrium points, fixed points, closed orbits, periodic solutions, and two-periodic solutions.
Thomas S. Parker, Leon O. Chua
Chapter 6. Stable and Unstable Manifolds
Abstract
In this chapter, we discuss the stable and unstable manifolds of an equilibrium point and of a fixed point. Stable and unstable manifolds are a useful tool for both the theorist and the simulator of nonlinear systems. As we shall see, under the proper conditions, the structure of the manifolds indicates the presence of Smale horseshoes which, in turn, implies sensitive dependence on initial conditions.
Thomas S. Parker, Leon O. Chua
Chapter 7. Dimension
Abstract
This chapter addresses the question of the dimension of a limit set, in particular, the dimension of a strange attractor. We will see that a strange attractor possesses non-integer dimension while the dimension of a non-chaotic attractor is always an integer.
Thomas S. Parker, Leon O. Chua
Chapter 8. Bifurcation Diagrams
Abstract
Consider an nth-order continuous-time system
$$\dot x = f(x,a)$$
(8.1)
with a parameter α ∈ ℝ. As α changes, the limit sets of the system also change. Typically, a small change in α produces small quantitative changes in a limit set. For instance, perturbing α could change the position of a limit set slightly, and if the limit set is not an equilibrium point, its shape or size could also change. There is also the possibility that a small change α a can cause a limit set to undergo a qualitative change. Such a qualitative change is called abifurcation and the value of α at which a bifurcation occurs is called a bifurcation value.
Thomas S. Parker, Leon O. Chua
Chapter 9. Programming
Abstract
A great deal of thought must go into the selection and development of the numerical algorithms used in a simulation program. It is also important to realize that an excellent numerical algorithm is useless if it is incorporated in a program that is awkward to use.
Thomas S. Parker, Leon O. Chua
Chapter 10. Phase Portraits
Abstract
In this, the last chapter, we examine some of the difficulties encountered in combining several numerical algorithms into a usable, intelligent, simulation program. The example used throughout this chapter is the INSITE program phase which draws phase portraits of two-dimensional autonomous continuous-time systems. An added benefit of this example is that we get to discuss in detail some properties of basins of attraction and their boundaries.
Thomas S. Parker, Leon O. Chua
Backmatter
Metadaten
Titel
Practical Numerical Algorithms for Chaotic Systems
verfasst von
Thomas S. Parker
Leon O. Chua
Copyright-Jahr
1989
Verlag
Springer New York
Electronic ISBN
978-1-4612-3486-9
Print ISBN
978-1-4612-8121-4
DOI
https://doi.org/10.1007/978-1-4612-3486-9