Chaos Introduction
Chaos theory is among the youngest of the sciences, and has rocketed from its obscure
roots in the seventies to become one of the most fascinating fields in existence.
At the forefront of much research on physical systems, and already being implemented
in fields covering as diverse matter as arrhythmic pacemakers, image compression, and
fluid dynamics, chaos science promises to continue to yield absorbing scientific
information which may shape the face of science in the future.
This is an introduction to chaos theory designed for those who have an
interest in chaos theory but are, very much like myself, confined by an
as yet underdeveloped mathematical background to theory over
mathematics. Seperate archives of seven varied topics in the area of
chaos theory are included, with graphics where necessary; a
bibliography
is also included for independent research.
The rest of this homepage is a quasi-FAQ which covers much of the basic
rationale and theory behind chaos theory.
Specific Topics
Bifurcation and Periodicity
Bifurcation Diagram
Physically Inspired Strange Attractors
Lorenz Attractor
Rossler Attractor
Henon Attractor
Astronomically Inspired Strange Attractors
Komogorov-Arnold-Moser Orbits
Fractal Geometry
Sierpinski Triangle
Von Koch Curve
Spleenwort Fern
Chaos Overview
What is chaos theory?
Formally, chaos theory is defined as the study of complex nonlinear dynamic
systems. Complex implies just that, nonlinear implies recursion
and higher mathematical algorithms, and dynamic implies nonconstant and
nonperiodic. Thus chaos theory is, very generally, the study of forever
changing complex systems based on mathematical concepts of recursion, whether
in the form of a recursive process or a set of differential equations modeling
a physical system.
For a more rigorous definition of chaos theory, it is advisable to visit the
much more scientific, much more broad-reaching chaos network definition, in
their excellent HTML document,
What
Is Chaos Theory?, also available in a
text
only version.
Misconceptions about chaos theory
Chaos theory has received some attention, beginning with its popularity in
movies such as Jurassic Park; public awareness of a science of
chaos has been steadily increasing. However, as with any media covered
item, many misconceptions have arisen concerning chaos theory.
The most commonly held misconception about chaos theory is that chaos
theory is about disorder. Nothing could be further from the truth!
Chaos theory is not about disorder! It does not
disprove determinism or dictate that ordered systems are impossible; it
does not invalidate experimental evidence or claim that modelling
complex systems is useless. The "chaos" in chaos theory is
order--not simply order, but the very ESSENCE of order.
It is true that chaos theory dictates that minor changes can cause
huge fluctuations. But one of the central concepts of chaos theory is that
while it is impossible to exactly predict the state of a system, it is
generally quite possible, even easy, to model the overall behavior
of a system. Thus, chaos theory lays emphasis not on the disorder
of the system--the inherent unpredictability of a system--but on the
order inherent in the system--the universal behavior of similar
systems.
Thus, it is incorrect to say that chaos theory is about disorder. To take
an example, consider
Lorenz's Attractor.
The Lorenz Attractor is based on three differential equations, three
constants, and three initial conditions. The attractor represents the
behavior of gas at any given time, and its condition at any given time
depends upon its condition at a previous time. If the initial conditions
are changed by even a tiny amount, say as tiny as the inverse of
Avogadro's number (a heinously small number with an order of 1E-24),
checking the attractor at a later time will yield numbers totally
different. This is because small differences will propagate themselves
recursively until numbers are entirely dissimilar to the original system
with the original initial conditions.
However, the plot of the attractor will look very much the same.
Both systems will have totally different values at any given time, and
yet the plot of the attractor--the overall behavior of the
system--will be the same.
Chaos theory predicts that complex nonlinear systems are inherently
unpredictable--but, at the same time, chaos theory also insures
that often, the way to express such an unpredictable system lies not in
exact equations, but in representations of the behavior of a
system--in plots of strange attractors or in fractals. Thus, chaos
theory, which many think is about unpredictability, is at the same time
about predictability in even the most unstable systems.
How is chaos theory applicable to the real world?
Everyone always wants to know one thing about new discoveries--what good are
they? So what good is chaos theory?
First and foremost, chaos theory is a theory. As such, much of it is
of use more as scientific background than as direct applicable knowledge.
Chaos theory is great as a way of looking at events which happen in the world
differently from the more traditional strictly deterministic view which has
dominated science from Newtonian times. Moviegoers who watched Jurassic
Park are surely aware that chaos theory can profoundly affect the way
someone thinks about the world; and indeed, chaos theory is useful as a
tool with which to interpret scientific data in new ways. Instead of a
traditional X-Y plot, scientists can now interpret phase-space diagrams
which--rather than describing the exact position of some variable with
respect to time--represents the overall behavior of a system.
Instead of looking for strict equations conforming to statistical data, we
can now look for dynamic systems with behavior similar in nature to
the statistical data--systems, that is, with similar attractors. Chaos
theory provides a sound framework with which to develop scientific
knowledge.
However, this is not to say that chaos theory has no applications in real
life.
Chaos theory techniques have been used to model biological systems, which
are of course some of the most chaotic systems imaginable. Systems of
dynamic equations have been used to model everything from population growth
to epidemics to arrhythmic heart palpitations.
In fact, almost any chaotic system can be readily modeled--the stock market
provides trends which can be analyzed with strange attractors more readily
than with conventional explicit equations; a dripping faucet seems random to
the untrained ear, but when plotted as a strange attractor, reveals an eerie
order unexpected by conventional means.
Fractals have cropped up everywhere, most notably in graphic applications
like the highly successful Fractal Design Painter series of products.
Fractal image compression techniques are still under research, but promise
such amazing results as 600:1 graphic compression ratios. The movie
special effects industry would have much less realistic clouds, rocks, and
shadows without fractal graphic technology.
And of course, chaos theory gives people a wonderfully interesting way to
become more interested in mathematics, one of the more unpopular pursuits
of the day.
Who were the pioneers of chaos theory?
Under Construction
Please stay with us as we continue to construct this page.
Bibliography
This is simply a list of books which address topics in chaos theory. This list does not
pretend to be either comprehensive or complete; it simply contains the paper-and-cardboard
equivalent of hypertext links. It is not presented in formal bibliographic format; you
probably will not require that and I certainly do not. Click on
bibliography.
This page was selected as selected as an outstanding website by
Webcrawler Select.
This page was cited in the "Tips and Links" section of the
Discovery Channel School
program "Wonders of Weather: Forecasting," scheduled to air on Assignment
Discovery on 2/14/96 with repeat airings on 4/3/96 and 5/22/96.
Assignment Discovery airs on Discovery Channel Monday-Friday, 9-10am ET/PT.
This site is referenced in the
sci.nonlinear FAQ
under the "Chaos Sites" heading.
This site is referenced by the wonderful
Chaos at Maryland site run by the
University of Maryland at College Park
under
"Nonlinear
Sites."
This site is linked to by
Andrew Ho,
its creator. He thinks it is cool.
This site is linked to by
Cyberina Flux
under
"stuff"
as a religion. I sort of like that.
This site is linked to by Ray and Jim from
Unplugged Software. They click-n
program.
This site is linked to by
Jon Nelson, designer of integrated
Customer Interactive
Systems.
This site is linked to by
Mingchao Shen of
Susquehanna University.
This site is linked to by
Eric Andersen
of Brown University.
This site is linked to by
Craig A. Hunter, professor
at William & Mary and researcher at
Langley.
This site is linked to by
Gabor Fenyes, math
nut, in his "Gabor's Favorite World Wide Web Links" section.
This site is linked to by
Steve Lee,
member of the educational institute
Tripod.
This site is linked to by
Zachary Harrison, yet another
member of the Doom religion.
This site is linked to by
Derrel Blain,
who maintains a beautiful site about chaos and symmetry.
This site is linked to by
Judy Ptre,
who considers the religious implications of chaos theory.
This site is linked to by
Diane Nyholt,
who has an intimate knowledge of chaos as a mother, in her
educational links.
This site is linked to by the Pomona, California chapter of the
Tau Alpha Pi Engineering
Technology Honor Society.
This site is linked to by the Harrisburg, Pennsylvania chapter of
ACM under "Favorite
Science Sites."
This site is linked to by
Bobby Hardenbrook under his
"Chaos in
Science" section.
This site was rated a
link of
the week by
Professor
John Dutcher of the
University of Guelph in Ontario,
Canada.
This page is linked to by French grad student
David Aubin of
Princeton.
This page was cited in Chris Braun's
final
exam for some class... :)
This page appears as a
science
"book" at the
Old Town
University
library.
Interesting comments on chaos theory as politics appear at this page on
Political Elements of
Strategic Planning for Technology.
This page is linked to by
Bonnie Lenore,
whose dissertation links chaos theory to composition and rhetoric.
This page is linked to by Austrian researcher
Rudolf H. Winger on his page of
science links.
This page is linked to by
Shane Beattie,
fellow Mathematica user.
This page is linked to by
Ronnie Joe Record under
Mathematics &
Science.
This page is linked to by PhD student
Warwick Tucker of Uppsala, Sweden,
who flatters me by using my marbled background. :)
This page is linked to in the vast
"Chaos, Complexity, and
Everything Else" list of
Lisa Landers of
Mercyhurst College.
This page is linked to by the
Visual Math Institute under
"Related
Pages."
This page is linked to by
Jeff of
Brock University in his discussion of
reality.
John Childs of Ontario has
a fascinating chaos theory "info-pak" available, which includes
an 8-page introduction to chaos theory and fractals, an MS-DOS format disk of
ten varied fractal-related programs, a Mandelbrot set postcard, and a
Mandelbrot set pin. The set is available for a mere $5; see
http://www.grenvillecc.ca/jchilds.
This page has been accessed
times since November 27, 1995.
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Andrew Ho
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