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This paper was written as an assignment for Ian Walton's Math G -Math for liberal Arts Students - at Mission College. If you use material from this paper, please acknowledge it.
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This paper was submitted by Michael Lacey for Math G at Mission College.
If you use material from this paper, please acknowledge it.
CHAOS THEORY
I never imagined that I would ever one day sit down and attempt to write an essay paper on Chaos Theory. As a matter of fact, I'd never even heard of Chaos Theory until we viewed a film that gave us a brief introduction to it during a class meeting one evening. I was impressed by the presentation and was literally "drawn in " by the science of Chaos.............. The event had much the same effect on me as that of the motion of a strange attractor....... I've always been very interested in science but I've never really been that good at mathematics.........and, as we all know, there is a mathematical correlation that runs between the two subjects. So , here I am.....I guess you could say that I'm initially a frustrated scientist.........traveling along a seemingly "deterministic" path of life, when suddenly my path is interrupted by a slight change in my initial condition, which has the effect of altering my direction. This experience in my life is a very simplistic scenario, it's true, and it describes an event that could very possibly lead to chaos. By the time we've arrived at the end of my paper, I'm certain that my path will have been forever changed through chaos.
Man has always been fascinated by the heavens. He's always sought out simple rules (explanations) or laws that govern the universe. Much of his attraction to the heavens, I'm sure, had to do with an appreciation for the sheer natural, physical beauty of the universe...............the brilliance of the millions of stars and planets...........sparkling within the seemingly endless blackness of space. The other part fueling this fascination for the heavens, no doubt, had to do with the curious nature of man. Man one night long ago, looked out into space and began to ponder the question of......What makes it all work? "How many are there.......".........How vast is it?.......What is the order?.......and "Why?" were perhaps just a few examples from a long lists of questions that were raised and pondered for years and years until some explanation was articulated that proved acceptable to the authors of the questions. Early Greek astronomers (circa 400B.C) worked out a mechanical system to explain the motions of the planets, This system was built on a geocentric (earth-centered) premise and taught that the planets, the sun, the moon and the stars all revolved around the Earth. Much later on (circa 1700) man had moved away from the geocentric theory and by 1720 most scientist and philosophers agreed that the sun was truly the center of the universe. At any rate.......it's always been important (perhaps it's curiosity or perhaps it's ego) for man to control things and be able to say that........."this is exactly the way it is today, right now at this moment........and that is the way it will be tomorrow." Isaac Newton theorized that the universe was a systematic organization of poetry in motion........ With clockwork precision.......The Sun, occupying the center space of the universe, with all the other planets and celestial bodies revolving in deterministic orbits around the center. Newton hypothesized that if two bodies attract each other with a force that was proportional to the square of the distance between them......the resulting motion of one body relative to the other could be shown in a mathematical curve called a conic section. This model or curve would embrace and further advance the supposition that a planet's path, moving under the effects of the Sun's gravity, would be elliptical and the the period of this motion would depend only on the average distance from the Sun. Armed with this information, Newton felt pretty good about his ability to make predictions based on this understanding of the universe. And for the most part, this understanding was correct. In Mathematical terms, Newton was able to demonstrate that the 'two-body' problem was integrable.......meaning that you could derive at a complete, practical solution to the problem by using relatively simple mathematical equations. Kepler's law of equal areas: the ratio of the square of the period and the cube of the semimajor axis (one-half the larger axis of an ellipse) is the same for all planets.
As Earth revolves about Planet
the Sun, equal areas are
swept out in equal periods
of time........
Where:
T= the period,
R= the semimajor axis
k= a constant that has the same value for all planets
The problem in this whole line of thinking lies within the premise.......that defines the Solar System as a 'two-body' system. Because the Solar System is not composed of just two bodies, other conditions (bodies) will undoubtedly effect Newton's clockwork equation.............throwing his orderly universe into a state conducive to chaotic behavior. It is true that the Sun's gravitational field dominates the motion of all planets. What was not taken into consideration was that the planets also have an influence on each other's motion. We are able to measure the effects of these "inter-planetary" influences, which are small, nonetheless significant. For example, The basic ellipse of the Earth's orbit is not fixed in space: it gradually rotates , or preccesses, at a current rate of 0.3 degrees per century due to
perturbations ("noise" / disturbances) by the other planets, most notably Jupiter. Newton was unable to to explain the chaos that occurs throughout the universe. He believed that the more information we gather about a particular thing we're observing, the more prepared we'll be to accurately predict things that will happen. It was believed and proposed that if you knew the position and speed of every, minute particle in the Universe, you would be able to predict it's future forever. This linear thinking will "......take you to the river, but it won't let you cross over".(Gosh!!.....that's something I heard my grandmother say many years ago that seems to be appropriate here.) This theory works only as long as the you're able to harness everything there is that can possibly have an effect on your system. Very deterministic..........very impossible. Deterministic meaning that you're accepting and using the past behavior of a system to predict it's future behavior........and impossible meaning that it simply will not work because of the chance of chaos and how chaos runs interference with all systems sensitive dependence on initial condition. Most of nature is composed of fluid, turbulent motion eg; water, wind, shifting earth, etc. Because of this fact, we'll never be able to predict the weather with 100% accuracy . Because of nature's sensitivity to initial conditions, there will always be a chaotic randomness associated with it. There will always be "other factors" (x) , that occur and will continue to take place in our universe, whose origins cannot be explained or predicted......... so we'll never have "all that there is or all that there could ever possibly be in any system." (I really hope that this is beginning to make sense to you).
Chaos, as I continue to cultivate and nurture a good definition that works for me, is a certain "controlled randomness" that occurs in nature. It's been explained as non-linear activity that is brought on by minute initial conditions. It's been explained further as time evolution with sensitive dependence on initial condition. (Ruelle, Chance and Chaos, pg.67) . Non-linear explains the path of a balloon flying wildly through space as is dispelled from it. Unpredictable moments and impossible to predict. Scientists cannot "control" non-linearity......thus chaos reigns over man.
The flapping of a single butterfly's wing today produces a tiny change in the state of the atmosphere. Over a period of time, what the atmosphere actually does diverges from what it would have done. So in a month's time, a tornado that would have devastated the Indonesian coast doesn't happen. Or maybe one that wasn't going to happen , does. (Ian Stewart, Does God Play Dice? The Mathematics of Chaos, pg.141).
We've seen this analogy used time and time again to explain chaos theory. It explains how a very small change in the initial conditions can drastically alter the long-term behavior of a system. I'd like to use a different analogy which helps me look at and better understand chaos theory. My analogy is a purely fun exploration, designed to entertain while, hopefully at the same time, provide a rather abstract "mental image" suggesting a chaos theory-like concept..... more so than it being suggested as scientific reality based on fact. We really have no way of knowing where our lives (paths) will take us and to a certain degree, our past, just as does our present, does play a significant role in influencing where we'll ultimately end up in the future. The choices we make now, combined with events of the past and the influences and dynamics we're subjected to daily, are all strong determining factors and must be considered in predicting the future. But, the bottom line is that we truly do not know, for sure, just where we'll end up. I'd like to begin my tale by first suggesting that reincarnation is live and well. I will attempt show to a parallel of (my) life cycles (side by side). Let us postulate further that our lives consists our own little personal systems that repeat over and over each time we die. The first list... (A).... represents a pattern of events (or describes a system) that has been taking place over the course of for past 4 periods (cycles) . The second list...(B)...represents my 5th cycle. This 5th. cycle starts off exactly the same as the previous 4, and runs it's course up to age 25. At age 25 while in route to the church to get married, I see a very young child being chased by a dog. I rescue the child from the dog and in the process I'm bitten on the hand by the dog. I then continue on to the wedding, a bit late and slightly wounded, but still in the mood for marriage. The small bite I received would later cause an infection leaving me sterile. This small change in the initial condition would drastically alter the long term behavior of my system.
The red copy indicates points in the 5th. cycle of life system that are very similar to points along the previous four systems, however because of the changes to the initial condition..............the system takes on a different look, although it does remain within the 85 year cycle as did the previous four cycles..
Michael's Life A list Michael's Life B list
Born 1952 (9 lbs. 10oz) Born 1952 ( 9 lbs. 10 oz.)
age 5...start Kindergarten age 5...start Kindergarten
age 17...graduate from H.S. age 17...Graduate from H.S.
age 22....Graduate from UCB age 22....Graduate from UCB
age 25....Marries Jill age 25...Bitten by dog / Marries Jill
age27.....First Job on Wall Street age 27...First job on Wall Street
age 30....twins born age 30...adopt young boy that I had rescued
age 45....Elected to Congress age 45...Elected to Congress
age 50....Elected to Senate age 50...son arrested for drugs / incident
age 58....Elected Pres. Of the Free World severely damages political career age 62.....Elected to 2nd term as Pres. age 58....son attempts suicide/ marriage ends
age 66.....retires from public life age 62 ...Runs for pres. against incumbent
age 85....dies of natural causes and looses badly age 66...admitted to insane asylum for attempting to bite public official age 85...death due to an undiagnosed slow spreading –rabies-like” disease contracted on wedding day. I realize that my little story is neither scientific nor is it an accurate representation of chaos theory..............but it does is graphically illustrate just how different a system may look when the dynamic forces making up that system are tinkered with, in even the slightest degree. My little story shows that whenever a "break" in the continuity of a system's history occurs.......it's past behavior no longer says anything about its long-term future behavior.
Conventional wisdom tells us that chaos represents a state of complete confusion. Webster further defines chaos as ......."the confusion of matter preceding the ordering of the universe." One of the most common misconceptions, with regards to the understanding and interpretation of chaos theory, is that chaos theory is all about disorder. Chaos theory is not solely about disorder......it does reference it .............but does not dwell long on it. Chaos does not disprove determinism, nor does it teach us that ordered systems are not possible. Chaos is more about the order making up a given system than it is about disorder. Chaos theory speaks to the very essence of order in that it teaches us about the universal behavior of similar systems. While proving to us that it's impossible to exactly predict the state of a system , it gives us information that allows us to model the overall behavior of a system. An excellent example of this fact is Lorenz's Attractor model. The Lorenz model is used to describe in a qualitative way the chaotic behavior of the evolution of weather regimes in the atmosphere. The positions of jet streams in our atmosphere can be used to define regimes (systems) that determine general patterns of weather experienced during a period of a week or more, unsettled or settled, for example. Gathering this information detailing feedback between the individual weather system instabilities and the larger scale flow (regime) is a non-linear process. The atmosphere (forced by heat energy from the Sun) is unstable and nonlinear. The attractor (model climate) is built on three different equations, three constants, and three initial conditions. It models or represents the behavior of gas at any given time, and the condition of that gas at any given time being dependent upon its condition at a previous time. If a change in the initial condition takes place by even the smallest degree...........checking the attractor at a later point in time will produce numbers totally different than the original numbers upon which the original system was built. The reasoning behind this is that one small change in the initial condition starts a cycle in which the effect of this change on that particular point in the system resonates through the system, (reproducing itself over and over again within the system) until a totally new system is born out of the original one. What's really amazing is that the plot of the attractor will look very much the same. Both systems will have totally different values at any given time............but the overall behavior of the system will be just as it was prior to the change. This behavior is represented by the "three-dimensional" model shown below. A state of instant 'weather' in the model can be represented by a point in the three-dimensional 'phase space' (opposed to 2-d space described in a flat plane), and the evolution of the weather with time can be represented by a line, or trajectory, in this space. There is no set number of times that a given trajectory must circle around within one of the "wings" of the attractor before it alters its path and whips off into a different direction . It could be once, or it could be 1000 times, depending on the position of the trajectory on the attractor.
The Lorenz attractor in the three-dimensional 'phase space' spanned by the model variables x, y, z
Although the three-component equations that Lorenz proposed do not realistically describe the evolution of weather regimes, they have similar chaotic properties to more realistic models. And as I stated previously.........the purpose of the model is to demonstrate overall universal behavior of similar systems.
The Lorenz Attractor ....A Description
The Lorenz attractors look rather like a mask with two else, but twisted so that the left and the right-hand sides bend in different directions. How can this lead to chaos? The answer is geometrical, and simple.......Trajectories wind around the two else of the mask, where both else merge together. Points that start off close together get stretched apart as they circulate around the attractor so they 'lose contact' , and can follow independent trajectories.......making the sequences of lefts and rights unpredictable in the long term. Stretching points apart and 're-enjecting' them back into small regions, is typical of all strange attractors. (Hall, pg 52)
References
Chance and Chaos................David Ruelle
Fundamentals of Physical Science.......J. T. Shipman; J.D.Wilson
Mathematical Ideas..........Miller; Heeren; Hornsby Jr.
Exploring Chaos..........Nina Hall
http://tqd.advanced.org/3120/main_content.html........(11/16/98)
Chaos and Non Linear Dynamics.........Hiborn
This paper was submitted by Michael Lacey for Math G at Mission College.
If you use material from this paper, please acknowledge it.
The Many Faces of
Chaos
I'm sure you'll agree that......not only does chaos perform a masterful job in it's description of the essence of order, it's also quite beautiful in it's own right , as can been appreciated in the "Many Faces of Chaos" displayed in the previous page.
Now.................I know that I'll never be a mathematician because mathematics is an area that I've just never seemed to acquire an affinity for. However, I do appreciate the discipline required to do good math. I'm really fascinated by science, but I'm also very realistic about my chances of ever becoming a scientist. I recognize the math correlation required to do good science, and as a result of this realization, I've been able to find a certain level of comfort in being a spectator of the discipline, rather than an active practitioner of the discipline. So...............having said all of that........what exactly have I learned about chaos theory as a result of this exercise? Well.......I've learned that it's a relatively new field of study and it's quite complex. I also discovered that most texts and resource books on the subject seem to be targeted to scientists and engineers. One has to be quite resourceful to find information on the topic that's written in layman terms. But putting all of that aside..............I've enjoyed my exploration into chaos because it's really been an "eye-opener" and it's given me a completely different way of looking at the world in which we live. I've discovered that systems encounter changes to the initial condition more frequently than I ever imagined.......and that the result, of these changes, actually causes the original system to "morph" to a totally new system that looks very much like the original system, yet it's quite different. I never imagined that such small, minute, changes could so dramatically effect anything (a system) until it was so very dynamically illustrated (for me) in the Lorenz's model. Another revelation for me was that I had never considered a system of order coming out of chaos (naturally). I'm a graphic designer and I've been trained with the understanding that the focus of good design is to bring order to chaos. When I stop and think about it .........chaos theory explores the order that comes about as a result of chaos..........So theoretically, chaos theory could actually speak to good design. (which would be supported by strange attractor modeling)
Chaos theory predicts that complex nonlinear systems are inherently unpredictable.......but simultaneously..........chaos theory teaches us that rather than attempting to express these unpredictable systems in exact equations, a greater windfall can be realized when we model the behavior of a given system in plots of strange attractors. Therefore.......chaos theory, rather than being solely a theory about unpredictability, is also about predictability in the most unstable systems.
Chaos Theory
An Exploration
By Michael Lacey
This paper was written as an assignment for Ian Walton's Math G -Math for liberal Arts Students - at Mission College. If you use material from this paper, please acknowledge it.