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Around mathematics and physics, chaos theory deals with a behavior of certain nonlinear dynamical systems that (under certain conditions) exhibit the phenomenon referred to as chaos, virtually all famously characterized by sensitivity to initial conditions (understand butterfly effect). Following of this sensitivity, a ascertained behavior of physical systems that exhibit chaos appears to become random, potentially though a model of the technique is 'deterministic' in the feel that these are swell defined & contains there is no random parameters. Examples of such systems include a atmosphere, the solar system, plate tectonics, turbulent fluids, economies, and people incubation.

Systems that exhibit mathematical chaos come deterministic and thus orderly inside a bit of feel; this technical indicator utilize of the word chaos is at odds by having most common idiom, which suggests complete disorder. View a article in chaos for a discussion of the origaround of the word in mythology, & more utilizes. Whenever i say that chaos theory studies deterministic systems, these are necessary to mention the related field of natural philosophy known as quantum chaos theory that studies non-deterministic systems following a laws of quantum mechanics.

Description of the theory
The non-linear dynamic formulas may, in the main, exhibit of these or even sir thomas more of the as a result types of behavior:

forever at rest forever expanding (single for unbounded systems) periodic motion quasi-periodic motion chaotic motion

a nature & severity of behavior a formulas will exhibit depends on the initial state of the body and the values of its parameters, whenever any. A virtually all hard nature & severity of behavior to characterize and predict is chaotic motion, the non-aperiodic complex motion which has given title to the theory.

Chaotic motion
Sequentially to classify a behavior of a formulwhen as chaotic, a rules must exhibit the charted properties:

it must exist as sensitive to initial conditions it must become transitive its periodical orbits must exist as dense

Sensitivity to initial conditions means that deuce points around such the rules might move inside immensely different flight in their phase space even if the difference in their initial configurations may be little. A systems behave identically only when their initial configurations were exactly a equivalent. An case of such sensitivity is the therefore-alleged "butterfly effect", whereby the flutter of the butterfly's wings is imagined to produce petite changes in a atmosphere which on top the course of period stimulator it to vary from either what it would use at times been & possibly induce something when spectacular as a tornado to occur. the butterfly flapping its wings is the chump change in the initial trouble of the body which is the causal agent of a chain of cases leading to big-shell phenomena rather tornadoes. Got a butterfly non flapped its wings, a flight of the formulas can stand been immensely different. More normally-known examples of chaotic motion come a commixture of coloured dyes and air flow turbulence.

Sensitivity to initial conditions is related to the Lyapunov exponent.

Transitivity means that applicatiin of the transformation on any given Interval I_1 stretches it until it overlaps by owning any more given Interval I_2.

Transitivity, heavy periodical points, & sensitivity to initial conditions potty completely become reach an arbitrary metric space. J. Banks & colleagues showed around 1992 that in the setting of the general metric space, transitivity & heavy periodical points together indicate sensitivity to initial conditions.

This simple however unexpected fact prompted Bau-Sen Du, of the Institute of Mathematics, Academithe Sinicthe, Taiwan to define a stronger version of sensitive dependence - extreme sensitive dependence - which is non a symptom of transitivity & heavy periodical points. Extreme sensitive dependence means, about, that points approximate separate & converge infinitely typically, when is typically a pack within examples of chaotic dynamic systems.

Attractors
Of these way of visualizing chaotic motion, or even indeed any nature and severity of motion, is to produce the phase diagram of the motion. Inside such the diagram period is inexplicit & apiece axis is of these dimension of the state. For example, 1 may plot a position of the pendulum against its velocity. The pendulum at rest is plotted as the point & a of these around periodic movement is plotted as a elementary closed curve. While such a plot forms the closed curve, the curve is known as an orbit. My pendulum has an infinite total of such orbits, forming the pencil of nested ellipses just about a origin.

Typically phase diagrams reveal that virtually all state flight wind higher approaching a bit of most common set boundaries. a rules ceases higher doing a equivalent motion for everthing initial states around a area around a motion, near when though the formulas is attracted thereto motion. Such attractive motion is suitably known as an attractor for the system & is very park for forced dissipative systems.

E.g., whenever you seize the damper to our pendulum, there are no matter what its initial position & speed it might wind higher existence at rest - or even additional right: it might email rest at a restrict. A flight on a phase diagram might altogether spiral within towards the middle, like than forming sets of ellipse. This point in a middle - a state while the pendulum is at rest - is known as an "attractor". Attractors come typically associated by owning dissipative systems like this, where a few element (a damper) dissipates energy.

Such an attractor can be known as the "point attractor". Non whole attractors come points. A few come elementary loops, or even extra complex doubled loops (for which wise shoppers want other than 2 degrees of freedom). & a few come actually fractals: the thus known as "strange attractors". Systems by owning loop attractors exhibit periodic movement. People sustaining other complex split loops tend to exhibit quasiperiodic motion. & systems by owning unknown attractors tend to exhibit chaotic behavior.

At any point around on a phase diagram, the rules might tend to develop to an additional neighboring state inside a few rather deterministic way. In case my pendulum is at the particular position & travelling sustaining the particular speed, i may calculate what its (infinitesimally) "next" position & speed is. That is, i personally might handle my phase diagram when existence the vector field, and utilise vector calculus to understand it. Attractors inside my phase diagram come just people regions by owning the veto divergence.

Strange attractors
When virtually all of the motion types mentioned above produce to super elementary attractors, prefer points & circle-like curves known as limit cycles, chaotic motion gives rise to what come referred to as strange attractors, attractors that can use outstanding detail & complexness. For example, the elementary 3-cubic model of the Lorenz weather system produce to the famed Lorenz attractor. the Lorenz attractor is perchance one of a right-known chaotic technique diagrams, probably because non single was it one of a number 1, however these are one of a virtually all complex & intrinsically gives rise to a super interesting pattern which looks such as the wings of a butterfly. An additional such attractor is the Rössler Map, which experiences cycle-both doubling route to chaos, rather a logistical map.

Unknown attractors occur around two continuous dynamical systems (such as a Lorenz body) & around a select few discrete systems (such as a Hénon map). More distinct dynamic systems have the repelling structure known as a Julia set which forms at the boundary between basins of attraction of fixed points - Julia sets may be thought of when unknown repellers. Each unknown attractors & Julia sets occasionally have a fractal structure.

A Poincaré-Bendixson theorem shows that the chaotic attractor even may lone arise inside a continuous dynamic body whenever it has ternion or further dimensions. All the same, there are no such restriction applies to distinct systems, which might exhibit unknown attractors around two or potentially a single miscreate systems.

History
A roots of chaos theory date back to astir 1900, in the studies of Henri Poincaré on a problem of the motion of tierce objects around reciprocal gravitational attraction, the therefore-alleged three-body problem. Poincaré uncovered that there may be orbits which are then aperiodic, & however non forever increasing nor approaching the fixed point. Late studies, likewise on the topic of nonlinear differential equations, were carried retired by G.D. Birkhoff, A.N. Kolmogorov, M.L. Cartwright, J.E. Littlewood, and Stephen Smale. Except for Smale, world health organization was peradventure a foremost pure mathematician to survey nonlinear kinetics, these studies were completely directly divine by physical science: a 3-system condition in the instance of Birkhoff, turbulence & astronomic problems in the pack of Kolmogorov, & radio engineering in the example of Cartwright & Littlewood. Although chaotic planetary motion got non been found, experimentalists experienced encountered turbulence inside fluid motion & aperiodic oscillation around radio circuits forswearing the profit of a theory to tell you what it were seeing.

Chaos theory progressed further apace whenever mid-century, when it 1st became evident for a few man of science that linear theory, a prevailing body theory at that instance, only may not teach you the ascertained behavior of certain experiments prefer that of the logistic map. A independent catalyst for a development of chaos theory was the electronic computer. Tremendously of a maths of chaos theory involves the perennial iteration of elementary mathematical system, which would exist as windy to handle hand. Electronic computers processed these perennial calculations practical. One of a earliest electronic digital computers, ENIAC, was used to redo elementary weather forecasting system.

An early pioneer of the theory was Edward Lorenz whose interest in chaos occur inadvertently across his operate in weather prediction in 1961. Lorenz was utilizing the basic computer, a Royal McBee LPG-30, to run his upwind simulation. He wanted to view a sequence of information again & to save period he began the simulation midmost of its course. He was respire to launder this by typing the printout of the information corresponding to conditions in the midst of his simulation which he experienced estimated survive instance.

To his surprise a weather condition condition that a machine began to predict was wholly different to the weather estimated prior to. Lorenz tracked this down to the computer printout. a printout rounded variables dispatch to a Terzetto-digit total, however the computer worked by having Cinque-digit figures. This difference is flyspeck & a consensus at a instance would stand been that it should will have practically there is no burden. Notwithstanding Lorenz got found that chump change within initial conditions produced big changes in the long-semipermanent effect.

A term chaos equally utilized around maths was coined per applied mathematician James A. Yorke.

Moore's law and the availability of cheaper computers broadens the applicability of chaos theory. Presently, chaos theory continues to become the super active region of the food and drug administration.

Mathematical theory
Mathematicians have devised numbers of extra ways to produce quantitative statements all about chaotic systems. These include:

fractal dimension of the attractor Lyapunov exponents recurrence plots Poincaré maps bifurcation diagrams Transfer operator

Minimum complexity of a chaotic system
Numbers of elementary systems can too develop chaos forgoing relying in differential equations, such as a logistic map, which is a difference equation (recurrence relation) that describes population incubation across instance.

Possibly discrete systems, such as cellular automata, can heavy depend in initial conditions. Stephen Wolfram has investigated a cellular automaton by owning this property, termed by him rule Thirty.

Other examples of chaotic systems
Double pendulum Logistic map Hénon map Lorenz model Smale horseshoe Dynamical billiards

Chaos at Maryland
Research group at the University of Maryland. Includes papers, gallery, database, abstracts, software, bibliography and contact.

Chaos: Making a New Science
Excerpt from the bestseller that brought the forefront of research to public eye. Includes illustrations and links.

CompLexicon
Terminology glossary about complex systems and chaotic dynamics.

Emergence of Chaos
Demonstrates how chaos emerges following a change in a parameter. Includes mathematical formulations and diagrams.

ChaosBook
Lecture notes on periodic orbits.

The Feigenbaum Fractal
Comprehensive analysis of the Feigenbaum set. Addresses mathematical and historical background.

Sci.nonlinear FAQ
FAQs collection from the sci.nonlinear newsgroup. Addresses basics, tutorial, applications and computational resources.

Chaos Research Group
Interdisciplinary research group at the University of Tennessee concerned with deterministic nonlinear dynamic aspects. Includes overview, publications, bibliography, monographs, glossary and project information.

Continued Fractions and Chaos
Scientific paper exploring some results of the theory of chaotic dynamical systems. Includes abstract, proceeding and references.

Society for Chaos Theory in Psychology and Life Sciences
Brings together researchers, theoreticians and practitioners interested in applying dynamical systems theory. Includes membership information, publications, meetings, tutorials and other resources.






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